660 research outputs found

    La cobotique

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    La cobotique constitue une nouvelle discipline technologique, Ă  l’interface de la cognitique et du facteur humain, de la biomĂ©canique et de la robotique. Ses dimensions applicatives concernent Ă  la fois les sciences humaines, l’ergonomie et la nouvelle problĂ©matique de l’usine du futur, mais Ă©galement les communications et les artefacts de compagnie. Si le progrĂšs des robots est conçu Ă  la mesure de son autonomie, celui des cobots est au contraire liĂ© de maniĂšre intime au comportement de l’homme auquel il est soumis pour augmenter Ă  la fois son comportement et sa cognition.Cobotics is a new technological discipline at the interface of cognitics and human factors, biomechanics and robotics. Its application relate to the human sciences, on one hand to ergonomics and the new issue of factory of the future, and on the other hand to communications and artefactial companions. If the progress of robots is caracterised by its autonomy, that of cobots is instead linked so intimately to human behavior for increasing its behavior and cognition

    Extracorporeal Membrane Oxygenation for Severe Acute Respiratory Distress Syndrome associated with COVID-19: An Emulated Target Trial Analysis.

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    RATIONALE: Whether COVID patients may benefit from extracorporeal membrane oxygenation (ECMO) compared with conventional invasive mechanical ventilation (IMV) remains unknown. OBJECTIVES: To estimate the effect of ECMO on 90-Day mortality vs IMV only Methods: Among 4,244 critically ill adult patients with COVID-19 included in a multicenter cohort study, we emulated a target trial comparing the treatment strategies of initiating ECMO vs. no ECMO within 7 days of IMV in patients with severe acute respiratory distress syndrome (PaO2/FiO2 <80 or PaCO2 ≄60 mmHg). We controlled for confounding using a multivariable Cox model based on predefined variables. MAIN RESULTS: 1,235 patients met the full eligibility criteria for the emulated trial, among whom 164 patients initiated ECMO. The ECMO strategy had a higher survival probability at Day-7 from the onset of eligibility criteria (87% vs 83%, risk difference: 4%, 95% CI 0;9%) which decreased during follow-up (survival at Day-90: 63% vs 65%, risk difference: -2%, 95% CI -10;5%). However, ECMO was associated with higher survival when performed in high-volume ECMO centers or in regions where a specific ECMO network organization was set up to handle high demand, and when initiated within the first 4 days of MV and in profoundly hypoxemic patients. CONCLUSIONS: In an emulated trial based on a nationwide COVID-19 cohort, we found differential survival over time of an ECMO compared with a no-ECMO strategy. However, ECMO was consistently associated with better outcomes when performed in high-volume centers and in regions with ECMO capacities specifically organized to handle high demand. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/)

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

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

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    An angular analysis of the B0→K∗0e+e−B^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 1.120 GeV2 ⁣/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 K∗0K^{*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 fb−1^{−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 B0→K∗0e+e−B^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 1.120 GeV2 ⁣/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 K∗0K^{*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

    A study of CP violation in B-+/- -&gt; DK +/- and B-+/- -&gt; D pi(+/-) decays with D -&gt; (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±→[KS0K∓π±]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 D‟0\overline{D}^0 meson, is performed. The analysis uses the LHCb data set collected in pppp collisions, corresponding to an integrated luminosity of 3 fb−1^{-1}. The analysis is sensitive to the CP-violating CKM phase Îł\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 Îł\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 Bs0→π+π−Ό+Ό−B_s^0 \to \pi^+\pi^-\mu^+\mu^- and B0→π+π−Ό+Ό−B^0 \to \pi^+\pi^-\mu^+\mu^- is performed in a data set corresponding to an integrated luminosity of 3.0 fb−1^{-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 Bs0→π+π−Ό+Ό−B_s^0 \to \pi^+\pi^-\mu^+\mu^- and the first evidence of the decay B0→π+π−Ό+Ό−B^0 \to \pi^+\pi^-\mu^+\mu^- are obtained and the branching fractions are measured to be B(Bs0→π+π−Ό+Ό−)=(8.6±1.5 (stat)±0.7 (syst)±0.7 (norm))×10−8\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(B0→π+π−Ό+Ό−)=(2.11±0.51 (stat)±0.15 (syst)±0.16 (norm))×10−8\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 B0→J/ψ(→Ό+Ό−)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−Ό+Ό− and B0→π+π−Ό+Ό− 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−Ό+Ό− and the first evidence of the decay B0→π+π−Ό+Ό− are obtained and the branching fractions, restricted to the dipion-mass range considered, are measured to be B(Bs0→π+π−Ό+Ό−)=(8.6±1.5 (stat)±0.7 (syst)±0.7(norm))×10−8 and B(B0→π+π−Ό+Ό−)=(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(→Ό+Ό−)K⁎(892)0(→K+π−) , used as a normalisation.A search for the rare decays Bs0→π+π−Ό+Ό− and B0→π+π−Ό+Ό− 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−Ό+Ό− and the first evidence of the decay B0→π+π−Ό+Ό− are obtained and the branching fractions, restricted to the dipion-mass range considered, are measured to be B(Bs0→π+π−Ό+Ό−)=(8.6±1.5 (stat)±0.7 (syst)±0.7(norm))×10−8 and B(B0→π+π−Ό+Ό−)=(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(→Ό+Ό−)K⁎(892)0(→K+π−) , used as a normalisation.A search for the rare decays Bs0→π+π−Ό+Ό−B_s^0 \to \pi^+\pi^-\mu^+\mu^- and B0→π+π−Ό+Ό−B^0 \to \pi^+\pi^-\mu^+\mu^- is performed in a data set corresponding to an integrated luminosity of 3.0 fb−1^{-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 Bs0→π+π−Ό+Ό−B_s^0 \to \pi^+\pi^-\mu^+\mu^- and the first evidence of the decay B0→π+π−Ό+Ό−B^0 \to \pi^+\pi^-\mu^+\mu^- are obtained and the branching fractions, restricted to the dipion-mass range considered, are measured to be B(Bs0→π+π−Ό+Ό−)=(8.6±1.5 (stat)±0.7 (syst)±0.7 (norm))×10−8\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(B0→π+π−Ό+Ό−)=(2.11±0.51 (stat)±0.15 (syst)±0.16 (norm))×10−8\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 B0→J/ψ(→Ό+Ό−)K∗(890)0(→K+π−)B^0\to J/\psi(\to \mu^+\mu^-)K^*(890)^0(\to K^+\pi^-), used as a normalisation

    Measurement of the Z plus b-jet cross-section in pp collisions at root s=7 TeV in the forward region

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    The associated production of a Z boson or an off-shell photon γ∗\gamma^* with a bottom quark in the forward region is studied using proton-proton collisions at a centre-of-mass energy of 7 TeV7{\mathrm{\,Te\kern -0.1em V}}. The Z bosons are reconstructed in the Z/Îłâˆ—â†’ÎŒ+Ό−{\text{Z}/\gamma^*}\rightarrow{\mu^{+}\mu^{-}} final state from muons with a transverse momentum larger than 20 GeV20{\mathrm{\,Ge\kern -0.1em V}}, while two transverse momentum thresholds are considered for jets (10 GeV10{\mathrm{\,Ge\kern -0.1em V}} and 20 GeV20{\mathrm{\,Ge\kern -0.1em V}}). Both muons and jets are reconstructed in the pseudorapidity range 2.010 GeV2.0 10{\mathrm{\,Ge\kern -0.1em V}}, and \sigma(\text{\text{Z}/\gamma^*(\mu^{+}\mu^{-})+b-jet}) = 167 \pm 47 (\text{stat}) \pm 29 (\text{syst}) \pm 6 (\text{lumi}) {\,{fb}} for {p_{\rm T}}(jet)>20 GeV>20{\mathrm{\,Ge\kern -0.1em V}}

    Measurement of Upsilon production in collisions at root s=2.76 TeV

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    The production of ΄(1S)\Upsilon(1S), ΄(2S)\Upsilon(2S) and ΄(3S)\Upsilon(3S) mesons decaying into the dimuon final state is studied with the LHCb detector using a data sample corresponding to an integrated luminosity of 3.3 pb−1pb^{-1} collected in proton-proton collisions at a centre-of-mass energy of s=2.76\sqrt{s}=2.76 TeV. The differential production cross-sections times dimuon branching fractions are measured as functions of the ΄\Upsilon transverse momentum and rapidity, over the ranges $p_{\rm T} Upsilon(1S) X) x B(Upsilon(1S) -> mu+mu-) = 1.111 +/- 0.043 +/- 0.044 nb, sigma(pp -> Upsilon(2S) X) x B(Upsilon(2S) -> mu+mu-) = 0.264 +/- 0.023 +/- 0.011 nb, sigma(pp -> Upsilon(3S) X) x B(Upsilon(3S) -> mu+mu-) = 0.159 +/- 0.020 +/- 0.007 nb, where the first uncertainty is statistical and the second systematic

    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−B^+\pi^- and B0π+B^0\pi^+ combinations are investigated in order to study excited B mesons. The analysis is based on a data sample corresponding to 3.0fb−13.0 fb^{-1} of pppp 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,+B_1(5721)^{0,+} and B2∗(5747)0,+B_2^*(5747)^{0,+} states are reported. Clear enhancements, particularly prominent at high pion transverse momentum, are seen over background in the mass range 58505850-60006000 MeV in both B+π−B^+\pi^- and B0π+B^0\pi^+ combinations. The structures are consistent with the presence of four excited B mesons, labelled BJ(5840)0,+B_J(5840)^{0,+} and BJ(5960)0,+B_J(5960)^{0,+}, whose masses and widths are obtained under different hypotheses for their quantum numbers.Invariant mass distributions of B+^{+} π−^{−} and B0^{0} π+^{+} combinations are investigated in order to study excited B mesons. The analysis is based on a data sample corresponding to 3.0 fb−1^{−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_{1}(5721)0,+^{0,+} and B2^{2}(5747)0,+^{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 B0^{0} π+^{+} combinations. The structures are consistent with the presence of four excited B mesons, labelled BJ_{J} (5840)0,+^{0,+} and BJ_{J} (5960)0,+^{0,+}, whose masses and widths are obtained under different hypotheses for their quantum numbers.Invariant mass distributions of B+pi- and B0pi+ 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 B_1(5721)^(0,+) and B_2*(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+pi- and B0pi+ combinations. The structures are consistent with the presence of four excited B mesons, labelled B_J(5840)^(0,+) and B_J(5960)^(0,+), whose masses and widths are obtained under different hypotheses for their quantum numbers
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