Amplitude Analysis of the B^{0}→K^{*0}μ^{+}μ^{-} Decay

An amplitude analysis of the B^{0}→K^{*0}μ^{+}μ^{-} decay is presented using a dataset corresponding to an integrated luminosity of 4.7  fb^{-1} of pp collision data collected with the LHCb experiment. For the first time, the coefficients associated to short-distance physics effects, sensitive to processes beyond the standard model, are extracted directly from the data through a q^{2}-unbinned amplitude analysis, where q^{2} is the μ^{+}μ^{-} invariant mass squared. Long-distance contributions, which originate from nonfactorizable QCD processes, are systematically investigated, and the most accurate assessment to date of their impact on the physical observables is obtained. The pattern of measured corrections to the short-distance couplings is found to be consistent with previous analyses of b- to s-quark transitions, with the largest discrepancy from the standard model predictions found to be at the level of 1.8 standard deviations. The global significance of the observed differences in the decay is 1.4 standard deviations.

Fraction of χ_{c} Decays in Prompt J/ψ Production Measured in pPb Collisions at sqrt[s_{NN}]=8.16 TeV

The fraction of χ_{c1} and χ_{c2} decays in the prompt J/ψ yield, F_{χ_{c}→J/ψ}=σ_{χ_{c}→J/ψ}/σ_{J/ψ}, is measured by the LHCb detector in pPb collisions at sqrt[s_{NN}]=8.16  TeV. The study covers the forward (1.5 Collapse

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Observation of Cabibbo-Suppressed Two-Body Hadronic Decays and Precision Mass Measurement of the Ω_{c}^{0} Baryon

The first observation of the singly Cabibbo-suppressed Ω_{c}^{0}→Ω^{-}K^{+} and Ω_{c}^{0}→Ξ^{-}π^{+} decays is reported, using proton-proton collision data at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5.4  fb^{-1}, collected with the LHCb detector between 2016 and 2018. The branching fraction ratios are measured to be B(Ω_{c}^{0}→Ω^{-}K^{+})/B(Ω_{c}^{0}→Ω^{-}π^{+})=[6.08±0.51(stat)±0.40(syst)]%,B(Ω_{c}^{0}→Ξ^{-}π^{+})/B(Ω_{c}^{0}→Ω^{-}π^{+})=[15.81±0.87(stat)±0.44(syst)±0.16(ext)]%. In addition, using the Ω_{c}^{0}→Ω^{-}π^{+} decay channel, the Ω_{c}^{0} baryon mass is measured to be M(Ω_{c}^{0})=2695.28±0.07(stat)±0.27(syst)±0.30(ext)  MeV, improving the precision of the previous world average by a factor of 4.

Enhanced Production of Λ_{b}^{0} Baryons in High-Multiplicity pp Collisions at sqrt[s]=13 TeV

The production rate of Λ_{b}^{0} baryons relative to B^{0} mesons in pp collisions at a center-of-mass energy sqrt[s]=13  TeV is measured by the LHCb experiment. The ratio of Λ_{b}^{0} to B^{0} production cross sections shows a significant dependence on both the transverse momentum and the measured charged-particle multiplicity. At low multiplicity, the ratio measured at LHCb is consistent with the value measured in e^{+}e^{-} collisions, and increases by a factor of ∼2 with increasing multiplicity. At relatively low transverse momentum, the ratio of Λ_{b}^{0} to B^{0} cross sections is higher than what is measured in e^{+}e^{-} collisions, but converges with the e^{+}e^{-} ratio as the momentum increases. These results imply that the evolution of heavy b quarks into final-state hadrons is influenced by the density of the hadronic environment produced in the collision. Comparisons with several models and implications for the mechanisms enforcing quark confinement are discussed.

Improved Measurement of CP Violation Parameters in B_{s}^{0}→J/ψK^{+}K^{-} Decays in the Vicinity of the ϕ(1020) Resonance

The decay-time-dependent CP asymmetry in B_{s}^{0}→J/ψ(→μ^{+}μ^{-})K^{+}K^{-} decays is measured using proton-proton collision data, corresponding to an integrated luminosity of 6  fb^{-1}, collected with the LHCb detector at a center-of-mass energy of 13 TeV. Using a sample of approximately 349 000 B_{s}^{0} signal decays with an invariant K^{+}K^{-} mass in the vicinity of the ϕ(1020) resonance, the CP-violating phase ϕ_{s} is measured, along with the difference in decay widths of the light and heavy mass eigenstates of the B_{s}^{0}-B[over ¯]_{s}^{0} system, ΔΓ_{s}, and the difference of the average B_{s}^{0} and B^{0} meson decay widths, Γ_{s}-Γ_{d}. The values obtained are ϕ_{s}=-0.039±0.022±0.006  rad, ΔΓ_{s}=0.0845±0.0044±0.0024  ps^{-1}, and Γ_{s}-Γ_{d}=-0.0056_{-0.0015}^{+0.0013}±0.0014  ps^{-1}, where the first uncertainty is statistical and the second systematic. These are the most precise single measurements to date and are consistent with expectations based on the Standard Model and with the previous LHCb analyses of this decay. These results are combined with previous independent LHCb measurements. The phase ϕ_{s} is also measured independently for each polarization state of the K^{+}K^{-} system and shows no evidence for polarization dependence.

Measurement of CP Violation in B^{0}→ψ(→ℓ^{+}ℓ^{-})K_{S}^{0}(→π^{+}π^{-}) Decays

A measurement of time-dependent CP violation in the decays of B^{0} and B[over ¯]^{0} mesons to the final states J/ψ(→μ^{+}μ^{-})K_{S}^{0}, ψ(2S)(→μ^{+}μ^{-})K_{S}^{0} and J/ψ(→e^{+}e^{-})K_{S}^{0} with K_{S}^{0}→π^{+}π^{-} is presented. The data correspond to an integrated luminosity of 6  fb^{-1} collected at a center-of-mass energy of sqrt[s]=13  TeV with the LHCb detector. The CP-violation parameters are measured to be S_{ψK_{S}^{0}}=0.717±0.013(stat)±0.008(syst) and C_{ψK_{S}^{0}}=0.008±0.012(stat)±0.003(syst). This measurement of S_{ψK_{S}^{0}} represents the most precise single measurement of the CKM angle β to date and is more precise than the current world average. In addition, measurements of the CP-violation parameters of the individual channels are reported and a combination with the LHCb Run 1 measurements is performed.

Observation of New Baryons in the Ξ_{b}^{-}π^{+}π^{-} and Ξ_{b}^{0}π^{+}π^{-} Systems

The first observation and study of two new baryonic structures in the final state Ξ_{b}^{0}π^{+}π^{-} and the confirmation of the Ξ_{b}(6100)^{-} state in the Ξ_{b}^{-}π^{+}π^{-} decay mode are reported using proton-proton collision data collected by the LHCb experiment, corresponding to an integrated luminosity of 9  fb^{-1}. In addition, the properties of the known Ξ_{b}^{*0}, Ξ_{b}^{'-} and Ξ_{b}^{*-} resonances are measured with improved precision. The new decay mode of the Ξ_{b}^{0} baryon to the Ξ_{c}^{+} π^{-} π^{+} π^{-} final state is observed and exploited for the first time in these measurements.

Precision Measurement of CP Violation in the Penguin-Mediated Decay B_{s}^{0}→ϕϕ

A flavor-tagged time-dependent angular analysis of the decay B_{s}^{0}→ϕϕ is performed using pp collision data collected by the LHCb experiment at the center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 6  fb^{-1}. The CP-violating phase and direct CP-violation parameter are measured to be ϕ_{s}^{ss[over ¯]s}=-0.042±0.075±0.009  rad and |λ|=1.004±0.030±0.009, respectively, assuming the same values for all polarization states of the ϕϕ system. In these results, the first uncertainties are statistical and the second systematic. These parameters are also determined separately for each polarization state, showing no evidence for polarization dependence. The results are combined with previous LHCb measurements using pp collisions at center-of-mass energies of 7 and 8 TeV, yielding ϕ_{s}^{ss[over ¯]s}=-0.074±0.069  rad and |λ|=1.009±0.030. This is the most precise study of time-dependent CP violation in a penguin-dominated B meson decay. The results are consistent with CP symmetry and with the standard model predictions.

Measurement of the Λ_{b}^{0}→Λ(1520)μ^{+}μ^{-} Differential Branching Fraction

The branching fraction of the rare decay Λ_{b}^{0}→Λ(1520)μ^{+}μ^{-} is measured for the first time, in the squared dimuon mass intervals q^{2}, excluding the J/ψ and ψ(2S) regions. The data sample analyzed was collected by the LHCb experiment at center-of-mass energies of 7, 8, and 13 TeV, corresponding to a total integrated luminosity of 9  fb^{-1}. The result in the highest q^{2} interval, q^{2}>15.0  GeV^{2}/c^{4}, where theoretical predictions have the smallest model dependence, agrees with the predictions.

Observation of New Ω_{c}^{0} States Decaying to the Ξ_{c}^{+}K^{-} Final State

Two new excited states, Ω_{c}(3185)^{0} and Ω_{c}(3327)^{0}, are observed in the Ξ_{c}^{+}K^{-} invariant-mass spectrum using proton-proton collision data collected by the LHCb experiment, corresponding to an integrated luminosity of 9  fb^{-1}. Five previously observed excited Ω_{c}^{0} states are confirmed, namely Ω_{c}(3000)^{0}, Ω_{c}(3050)^{0}, Ω_{c}(3065)^{0}, Ω_{c}(3090)^{0}, and Ω_{c}(3119)^{0}. The masses and widths of these seven states are measured with the highest precision to date.

Evidence of a J/ψK_{S}^{0} Structure in B^{0}→J/ψϕK_{S}^{0} Decays

An amplitude analysis of B^{0}→J/ψϕK_{S}^{0} decays is performed using proton-proton collision data, corresponding to an integrated luminosity of 9  fb^{-1}, collected with the LHCb detector at center-of-mass energies of 7, 8, and 13 TeV. Evidence with a significance of 4.0 standard deviations of a structure in the J/ψK_{S}^{0} system, named T_{ψs1}^{θ}(4000)^{0}, is seen, with its mass and width measured to be 3991_{-10}^{+12} _{-17}^{+9}  MeV/c^{2} and 105_{-25}^{+29} _{-23}^{+17}  MeV, respectively, where the first uncertainty is statistical and the second systematic. The T_{ψs1}^{θ}(4000)^{0} state is likely to be the isospin partner of the T_{ψs1}^{θ}(4000)^{+} state, previously observed in the J/ψK^{+} system of the B^{+}→J/ψϕK^{+} decay. When isospin symmetry for the charged and neutral T_{ψs1}^{θ}(4000) states is assumed, the signal significance increases to 5.4 standard deviations.

Measurement of the Ratios of Branching Fractions R(D^{*}) and R(D^{0})

The ratios of branching fractions R(D^{*})≡B(B[over ¯]→D^{*}τ^{-}ν[over ¯]_{τ})/B(B[over ¯]→D^{*}μ^{-}ν[over ¯]_{μ}) and R(D^{0})≡B(B^{-}→D^{0}τ^{-}ν[over ¯]_{τ})/B(B^{-}→D^{0}μ^{-}ν[over ¯]_{μ}) are measured, assuming isospin symmetry, using a sample of proton-proton collision data corresponding to 3.0  fb^{-1} of integrated luminosity recorded by the LHCb experiment during 2011 and 2012. The tau lepton is identified in the decay mode τ^{-}→μ^{-}ν_{τ}ν[over ¯]_{μ}. The measured values are R(D^{*})=0.281±0.018±0.024 and R(D^{0})=0.441±0.060±0.066, where the first uncertainty is statistical and the second is systematic. The correlation between these measurements is ρ=-0.43. The results are consistent with the current average of these quantities and are at a combined 1.9 standard deviations from the predictions based on lepton flavor universality in the standard model.

Measurement of the Prompt D^{0} Nuclear Modification Factor in p-Pb Collisions at sqrt[s_{NN}]=8.16 TeV

The production of prompt D^{0} mesons in proton-lead collisions in both the forward and backward rapidity regions at a center-of-mass energy per nucleon pair of sqrt[s_{NN}]=8.16  TeV is measured by the LHCb experiment. The nuclear modification factor of prompt D^{0} mesons is determined as a function of the transverse momentum p_{T}, and the rapidity in the nucleon-nucleon center-of-mass frame y^{*}. In the forward rapidity region, significantly suppressed production with respect to pp collisions is measured, which provides significant constraints on models of nuclear parton distributions and hadron production down to the very low Bjorken-x region of ∼10^{-5}. In the backward rapidity region, a suppression with a significance of 2.0-3.8 standard deviations compared to parton distribution functions in a nuclear environment expectations is found in the kinematic region of p_{T}>6  GeV/c and -3.25 Collapse

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Measurement of the Time-Integrated CP Asymmetry in D^{0}→K^{-}K^{+} Decays

The time-integrated CP asymmetry in the Cabibbo-suppressed decay D^{0}→K^{-}K^{+} is measured using proton-proton collision data, corresponding to an integrated luminosity of 5.7  fb^{-1} collected at a center-of-mass energy of 13 TeV with the LHCb detector. The D^{0} mesons are required to originate from promptly produced D^{*+}→D^{0}π^{+} decays, and the charge of the companion pion is used to determine the flavor of the charm meson at production. The time-integrated CP asymmetry is measured to be A_{CP}(K^{-}K^{+})=[6.8±5.4±1.6]×10^{-4} where the first uncertainty is statistical and the second systematic. The direct CP asymmetries in D^{0}→K^{-}K^{+} and D^{0}→π^{-}π^{+} decays, a_{K^{-}K^{+}}^{d} and a_{π^{-}π^{+}}^{d}, are derived by combining A_{CP}(K^{-}K^{+}) with the time-integrated CP asymmetry difference, ΔA_{CP}=A_{CP}(K^{-}K^{+})-A_{CP}(π^{-}π^{+}), and other inputs, giving a_{K^{-}K^{+}}^{d}=(7.7±5.7)×10^{-4},a_{π^{-}π^{+}}^{d}=(23.2±6.1)×10^{-4},with a correlation coefficient corresponding to ρ=0.88. The compatibility of these results with CP symmetry is 1.4 and 3.8 standard deviations for D^{0}→K^{-}K^{+} and D^{0}→π^{-}π^{+} decays, respectively. This is the first evidence for direct CP violation in a specific D^{0} decay.

Measurement of the Branching Fractions B(B^{0}→pp[over ¯]pp[over ¯]) and B(B_{s}^{0}→pp[over ¯]pp[over ¯])

Searches for the rare hadronic decays B^{0}→pp[over ¯]pp[over ¯] and B_{s}^{0}→pp[over ¯]pp[over ¯] are performed using proton-proton collision data recorded by the LHCb experiment and corresponding to an integrated luminosity of 9  fb^{-1}. Significances of 9.3σ and 4.0σ, including statistical and systematic uncertainties, are obtained for the B^{0}→pp[over ¯]pp[over ¯] and B_{s}^{0}→pp[over ¯]pp[over ¯] signals, respectively. The branching fractions are measured relative to the topologically similar normalization decays B^{0}→J/ψ(→pp[over ¯])K^{*0}(→K^{+}π^{-}) and B_{s}^{0}→J/ψ(→pp[over ¯])⁢ϕ(→K^{+}K^{-}). The branching fractions are measured to be B(B^{0}→pp[over ¯]pp[over ¯])=(2.2±0.4±0.1±0.1)×10^{-8} and B(B_{s}^{0}→pp[over ¯]pp[over ¯])=(2.3±1.0±0.2±0.1)×10^{-8}. In these measurements, the first uncertainty is statistical, the second is systematic, and the third one is due to the external branching fraction of the normalization channel.

Observation of a Resonant Structure near the D_{s}^{+}D_{s}^{-} Threshold in the B^{+}→D_{s}^{+}D_{s}^{-}K^{+} Decay

An amplitude analysis of the B^{+}→D_{s}^{+}D_{s}^{-}K^{+} decay is carried out to study for the first time its intermediate resonant contributions, using proton-proton collision data collected with the LHCb detector at center-of-mass energies of 7, 8, and 13 TeV. A near-threshold peaking structure, referred to as X(3960), is observed in the D_{s}^{+}D_{s}^{-} invariant-mass spectrum with significance greater than 12 standard deviations. The mass, width, and the quantum numbers of the structure are measured to be 3956±5±10  MeV, 43±13±8  MeV, and J^{PC}=0^{++}, respectively, where the first uncertainties are statistical and the second systematic. The properties of the new structure are consistent with recent theoretical predictions for a state composed of cc[over ¯]ss[over ¯] quarks. Evidence for an additional structure is found around 4140 MeV in the D_{s}^{+}D_{s}^{-} invariant mass, which might be caused either by a new resonance with the 0^{++} assignment or by a J/ψϕ↔D_{s}^{+}D_{s}^{-} coupled-channel effect.

Evidence for Modification of b Quark Hadronization in High-Multiplicity pp Collisions at sqrt[s]=13 TeV

The production rate of B_{s}^{0} mesons relative to B^{0} mesons is measured by the LHCb experiment in pp collisions at a center-of-mass energy sqrt[s]=13  TeV over the forward rapidity interval 2 Collapse

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Test of Lepton Universality in b→sℓ^{+}ℓ^{-} Decays

The first simultaneous test of muon-electron universality using B^{+}→K^{+}ℓ^{+}ℓ^{-} and B^{0}→K^{*0}ℓ^{+}ℓ^{-} decays is performed, in two ranges of the dilepton invariant-mass squared, q^{2}. The analysis uses beauty mesons produced in proton-proton collisions collected with the LHCb detector between 2011 and 2018, corresponding to an integrated luminosity of 9  fb^{-1}. Each of the four lepton universality measurements reported is either the first in the given q^{2} interval or supersedes previous LHCb measurements. The results are compatible with the predictions of the Standard Model.

First Observation of a Doubly Charged Tetraquark and Its Neutral Partner

A combined amplitude analysis is performed for the decays B^{0}→D[over ¯]^{0}D_{s}^{+}π^{-} and B^{+}→D^{-}D_{s}^{+}π^{+}, which are related by isospin symmetry. The analysis is based on data collected by the LHCb detector in proton-proton collisions at center-of-mass energies of 7, 8, and 13 TeV. The full data sample corresponds to an integrated luminosity of 9  fb^{-1}. Two new resonant states with masses of 2.908±0.011±0.020  GeV and widths of 0.136±0.023±0.013  GeV are observed, which decay to D_{s}^{+}π^{+} and D_{s}^{+}π^{-} respectively. The former state indicates the first observation of a doubly charged open-charm tetraquark state with minimal quark content [cs[over ¯]ud[over ¯]], and the latter state is a neutral tetraquark composed of [cs[over ¯]u[over ¯]d] quarks. Both states are found to have spin-parity of 0^{+}, and their resonant parameters are consistent with each other, which suggests that they belong to an isospin triplet.

Search for Rare Decays of D^{0} Mesons into Two Muons

A search for the very rare D^{0}→μ^{+}μ^{-} decay is performed using data collected by the LHCb experiment in proton-proton collisions at sqrt[s]=7, 8, and 13 TeV, corresponding to an integrated luminosity of 9  fb^{-1}. The search is optimized for D^{0} mesons from D^{*+}→D^{0}π^{+} decays but is also sensitive to D^{0} mesons from other sources. No evidence for an excess of events over the expected background is observed. An upper limit on the branching fraction of this decay is set at B(D^{0}→μ^{+}μ^{-})<3.1×10^{-9} at a 90% C.L. This represents the world's most stringent limit, constraining models of physics beyond the standard model.

Nuclear Modification Factor of Neutral Pions in the Forward and Backward Regions in p-Pb Collisions

The nuclear modification factor of neutral pions is measured in proton-lead collisions collected at a center-of-mass energy per nucleon of 8.16 TeV with the LHCb detector. The π^{0} production cross section is measured differentially in transverse momentum (p_{T}) for 1.5 Collapse

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Observation of a J/ψΛ Resonance Consistent with a Strange Pentaquark Candidate in B^{-}→J/ψΛp[over ¯] Decays

An amplitude analysis of B^{-}→J/ψΛp[over ¯] decays is performed using 4400 signal candidates selected on a data sample of pp collisions recorded at center-of-mass energies of 7, 8, and 13 TeV with the LHCb detector, corresponding to an integrated luminosity of 9  fb^{-1}. A narrow resonance in the J/ψΛ system, consistent with a pentaquark candidate with strangeness, is observed with high significance. The mass and the width of this new state are measured to be 4338.2±0.7±0.4  MeV and 7.0±1.2±1.3  MeV, where the first uncertainty is statistical and the second systematic. The spin is determined to be 1/2 and negative parity is preferred. Because of the small Q-value of the reaction, the most precise single measurement of the B^{-} mass to date, 5279.44±0.05±0.07  MeV, is obtained.

First Measurement of the Z→μ^{+}μ^{-} Angular Coefficients in the Forward Region of pp Collisions at sqrt[s]=13 TeV

The first study of the angular distribution of μ^{+}μ^{-} pairs produced in the forward rapidity region via the Drell-Yan reaction pp→γ^{*}/Z+X→ℓ^{+}ℓ^{-}+X is presented, using data collected with the LHCb detector at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5.1  fb^{-1}. The coefficients of the five leading terms in the angular distribution are determined as a function of the dimuon transverse momentum and rapidity. The results are compared to various theoretical predictions of the Z-boson production mechanism and can also be used to probe transverse-momentum-dependent parton distributions within the proton.

Study of the doubly charmed tetraquark [Formula: see text]

Quantum chromodynamics, the theory of the strong force, describes interactions of coloured quarks and gluons and the formation of hadronic matter. Conventional hadronic matter consists of baryons and mesons made of three quarks and quark-antiquark pairs, respectively. Particles with an alternative quark content are known as exotic states. Here a study is reported of an exotic narrow state in the D0D0π+ mass spectrum just below the D*+D0 mass threshold produced in proton-proton collisions collected with the LHCb detector at the Large Hadron Collider. The state is consistent with the ground isoscalar [Formula: see text] tetraquark with a quark content of [Formula: see text] and spin-parity quantum numbers JP = 1+. Study of the DD mass spectra disfavours interpretation of the resonance as the isovector state. The decay structure via intermediate off-shell D*+ mesons is consistent with the observed D0π+ mass distribution. To analyse the mass of the resonance and its coupling to the D*D system, a dedicated model is developed under the assumption of an isoscalar axial-vector [Formula: see text] state decaying to the D*D channel. Using this model, resonance parameters including the pole position, scattering length, effective range and compositeness are determined to reveal important information about the nature of the [Formula: see text] state. In addition, an unexpected dependence of the production rate on track multiplicity is observed.

Angular Analysis of D^{0}→π^{+}π^{-}μ^{+}μ^{-} and D^{0}→K^{+}K^{-}μ^{+}μ^{-} Decays and Search for CP Violation

The first full angular analysis and an updated measurement of the decay-rate CP asymmetry of the D^{0}→π^{+}π^{-}μ^{+}μ^{-} and D^{0}→K^{+}K^{-}μ^{+}μ^{-} decays are reported. The analysis uses proton-proton collision data collected with the LHCb detector at center-of-mass energies of 7, 8, and 13 TeV. The dataset corresponds to an integrated luminosity of 9  fb^{-1}. The full set of CP -averaged angular observables and their CP asymmetries are measured as a function of the dimuon invariant mass. The results are consistent with expectations from the standard model and with CP symmetry.

Immune-endocrine biomarkers associated with mental health: a 9-year longitudinal investigation from the Hertfordshire Ageing Study

Introduction

Ageing is accompanied by the development of low-grade systemic inflammation which may promote changes in the neural systems predisposing to geriatric depression via the hypothalamic-pituitary-adrenal (HPA) axis.

Objectives

The aim of this study was to investigate the longitudinal associations between baseline values and conditional changes in immune-endocrine biomarkers and mental health status in a population-based cohort of older adults.

Methods

Data from 347 subjects(200 men, 147 women) who participated in the Hertfordshire Ageing Study at baseline(mean age 67.3 years) and at 9-year follow-up were analysed. Serum samples for analysis of inflammatory and endocrinological measures were collected at baseline and follow-up. At follow-up, depression (Hospital Anxiety and Depression Scale) and mental health(Short Form-36 questionnaire) were assessed. Baseline values and changes in biomarkers in relation to risk of high depression scores and low mental health scores were examined using logistic regression.

Results

Lower baseline cortisol was related to greater risk of high depression scores; higher baseline cortisol: Dehydroepiandrosterone Sulphate ratio(men only) and higher baseline CRP(women only) were related to greater risk of poor mental health scores. In addition, greater decline in cortisol was related to increased risk of high depression scores among men. These relationships were robust(p<0.05) after controlling for sex, age, BMI, smoking, alcohol consumption and number of systems medicated.

Conclusions

This study provides further evidence of the role of the HPA and inflammation in older adults with poor mental health. In addition, the findings highlight sex differences where increased inflammation in women and declines in cortisol in men was linked to poorer mental health.

Disclosure

No significant relationships.

Inflammatory Markers in Obsessive-Compulsive Disorder: A Systematic Review and Meta-Analysis

Introduction

A growing number of studies have examined the link between inflammatory markers (IM) and the pathophysiology of obsessive-compulsive disorder (OCD). However, this association has yet to be fully identified.

Objectives

This review aims to systematically evaluate evidence from studies examining peripheral IM in adult participants with OCD compared to controls. IM included: CRP, TNFa, IFNγ, IL1/4/6/10.

Methods

Databases used for literature searching: Medline, Embase, PsycINFO (until October 2021). Studies that examined IM in the blood of adult OCD and control groups were included. Screening and data extraction adhered to PRISMA guideline standards. The quality assessment utilised funnel plots and the approach developed by Hawker et al. 2002. A random-effects meta-analysis model was adopted. PROSPERO reference number: CRD42021284766.

Results

The systematic review (19 studies, 1,225 participants) and meta-analysis (12 studies, 796 participants) had an average quality assessment score of 28.3 (medium quality) and 30.7 (high quality), respectively. The average heterogeneity of each IM analysed was 76.6%. Totalled, each study and IM analysis showed more insignificant differences (n=35) than significant differences (n=25). The meta-analysis revealed no significant difference for overall IM assessments. However, a sub-analysis of IL6 (excluding studies using serum or lipopolysaccharide stimulation) found significantly lower levels of IL6 within the OCD group (effect size: 3.98 and 95% CI: 0.43,7.53).

Conclusions

This is an up-to-date systematic review examining IM in OCD. Insignificant results found may have resulted from the relatively high heterogeneity or varied study designs. One sub-analysis of IL6 identified an association, although further studies are required with larger sample sizes and fewer disparities.

Disclosure

No significant relationships.

Tests of Lepton Universality Using B^{0}→K_{S}^{0}ℓ^{+}ℓ^{-} and B^{+}→K^{*+}ℓ^{+}ℓ^{-} Decays

Tests of lepton universality in B^{0}→K_{S}^{0}ℓ^{+}ℓ^{-} and B^{+}→K^{*+}ℓ^{+}ℓ^{-} decays where ℓ is either an electron or a muon are presented. The differential branching fractions of B^{0}→K_{S}^{0}e^{+}e^{-} and B^{+}→K^{*+}e^{+}e^{-} decays are measured in intervals of the dilepton invariant mass squared. The measurements are performed using proton-proton collision data recorded by the LHCb experiment, corresponding to an integrated luminosity of 9  fb^{-1} . The results are consistent with the standard model and previous tests of lepton universality in related decay modes. The first observation of B^{0}→K_{S}^{0}e^{+}e^{-} and B^{+}→K^{*+}e^{+}e^{-} decays is reported.

Observation of the Decay Λ_{b}^{0}→Λ_{c}^{+}τ^{-}ν[over ¯]_{τ}

The first observation of the semileptonic b-baryon decay Λ_{b}^{0}→Λ_{c}^{+}τ^{-}ν[over ¯]_{τ}, with a significance of 6.1σ, is reported using a data sample corresponding to 3  fb^{-1} of integrated luminosity, collected by the LHCb experiment at center-of-mass energies of 7 and 8 TeV at the LHC. The τ^{-} lepton is reconstructed in the hadronic decay to three charged pions. The ratio K=B(Λ_{b}^{0}→Λ_{c}^{+}τ^{-}ν[over ¯]_{τ})/B(Λ_{b}^{0}→Λ_{c}^{+}π^{-}π^{+}π^{-}) is measured to be 2.46±0.27±0.40, where the first uncertainty is statistical and the second systematic. The branching fraction B(Λ_{b}^{0}→Λ_{c}^{+}τ^{-}ν[over ¯]_{τ})=(1.50±0.16±0.25±0.23)% is obtained, where the third uncertainty is from the external branching fraction of the normalization channel Λ_{b}^{0}→Λ_{c}^{+}π^{-}π^{+}π^{-}. The ratio of semileptonic branching fractions R(Λ_{c}^{+})≡B(Λ_{b}^{0}→Λ_{c}^{+}τ^{-}ν[over ¯]_{τ})/B(Λ_{b}^{0}→Λ_{c}^{+}μ^{-}ν[over ¯]_{μ}) is derived to be 0.242±0.026±0.040±0.059, where the external branching fraction uncertainty from the channel Λ_{b}^{0}→Λ_{c}^{+}μ^{-}ν[over ¯]_{μ} contributes to the last term. This result is in agreement with the standard model prediction.

[Screening and analysis of prognostic factors of repairing single missing tooth by autotransplantation of teeth]

Objective: To screen and analyze the factors affecting the prognosis of replacing single missing tooth by autograft tooth, so as to provide reference for clinical judgment of surgical prognosis. Methods: A total of 176 patients (188 teeth) underwent autotransplantation of teeth in the Department of Oral & Maxillofacial Surgery, School of Stomatology, The Fourth Military Medical University from January 2017 to December 2019, including 85 teeth of males and 103 teeth of females were involved. The age was (33.0±9.8) years (16-65 years). The possible factors affecting the prognosis of replacing single missing tooth by autograft tooth were summarized and grouped, and the clinical and imaging data were recorded and judged. The surgical records and photographic data from the patients' previous medical records were retrospectively analyzed. The survival analysis method was used for statistical analysis to screen out the factors affecting the cumulative survival rate of transplanted teeth. Results: The 5-year cumulative survival rate of 188 transplanted teeth was 88.4%. Univariate Log-Rank analysis showed that age (P<0.001), sex (P=0.008), smoking (P<0.001), position of recipient area (P<0.001), height of alveolar bone in recipient area (P<0.001), time of donor tooth in vitro (P<0.001), use of donor model (P<0.001) and initial stability (P<0.001) were significantly correlated with cumulative survival rate of transplanted teeth. Multivariate Cox proportional hazard regression analysis showed that smoking (β=-2.812, P=0.049), alveolar bone height (β=1.521, P=0.020), donor time (β=-2.001, P=0.019), use of donor model (β=1.666, P=0.034) and initial stability (β=-1.417, P=0.033) were significantly correlated with the cumulative survival rate of transplanted teeth. Conclusions: The prognosis of autogenous tooth transplantation can be predicted by smoking, height of alveolar bone in recipient area, time of donor teeth in vitro, use of donor model and initial stability. Good prognosis of transplanted teeth can be obtained by using donor model during operation, reducing the time of donor teeth in vitro, taking effective methods to restore alveolar bone height, maintaining good initial stability, and good oral health education after operation.

Observation of Two New Excited Ξ_{b}^{0} States Decaying to Λ_{b}^{0}K^{-}π^{+}

Two narrow resonant states are observed in the Λ_{b}^{0}K^{-}π^{+} mass spectrum using a data sample of proton-proton collisions at a center-of-mass energy of 13 TeV, collected by the LHCb experiment and corresponding to an integrated luminosity of 6  fb^{-1}. The minimal quark content of the Λ_{b}^{0}K^{-}π^{+} system indicates that these are excited Ξ_{b}^{0} baryons. The masses of the Ξ_{b}(6327)^{0} and Ξ_{b}(6333)^{0} states are m[Ξ_{b}(6327)^{0}]=6327.28_{-0.21}^{+0.23}±0.12±0.24 and m[Ξ_{b}(6333)^{0}]=6332.69_{-0.18}^{+0.17}±0.03±0.22  MeV, respectively, with a mass splitting of Δm=5.41_{-0.27}^{+0.26}±0.12  MeV, where the uncertainties are statistical, systematic, and due to the Λ_{b}^{0} mass measurement. The measured natural widths of these states are consistent with zero, with upper limits of Γ[Ξ_{b}(6327)^{0}]<2.20(2.56) and Γ[Ξ_{b}(6333)^{0}]<1.60(1.92)  MeV at a 90% (95%) credibility level. The significance of the two-peak hypothesis is larger than nine (five) Gaussian standard deviations compared to the no-peak (one-peak) hypothesis. The masses, widths, and resonant structure of the new states are in good agreement with the expectations for a doublet of 1D Ξ_{b}^{0} resonances.

Study of Z Bosons Produced in Association with Charm in the Forward Region

Events containing a Z boson and a charm jet are studied for the first time in the forward region of proton-proton collisions. The data sample used corresponds to an integrated luminosity of 6  fb^{-1} collected at a center-of-mass energy of 13 TeV with the LHCb detector. In events with a Z boson and a jet, the fraction of charm jets is determined in intervals of Z-boson rapidity in the range 2.0<y(Z)<4.5. A sizable enhancement is observed in the forwardmost y(Z) interval, which could be indicative of a valencelike intrinsic-charm component in the proton wave function.

Identification of Immune-Cell-Related Prognostic Biomarkers of Esophageal Squamous Cell Carcinoma Based on Tumor Microenvironment

Background

Esophageal squamous cell carcinoma (ESCC) is one of the most fatal cancers in the world. The 5-year survival rate of ESCC is <30%. However, few biomarkers can accurately predict the prognosis of patients with ESCC. We aimed to identify potential survival-associated biomarkers for ESCC to improve its poor prognosis.

Methods

ImmuneAI analysis was first used to access the immune cell abundance of ESCC. Then, ESTIMATE analysis was performed to explore the tumor microenvironment (TME), and differential analysis was used for the selection of immune-related differentially expressed genes (DEGs). Weighted gene coexpression network analysis (WGCNA) was used for selecting the candidate DEGs. Least absolute shrinkage and selection operator (LASSO) Cox regression was used to build the immune-cell-associated prognostic model (ICPM). Kaplan–Meier curve of survival analysis was performed to evaluate the efficacy of the ICPM.

Results

Based on the ESTIMATE and ImmuneAI analysis, we obtained 24 immune cells’ abundance. Next, we identified six coexpression module that was associated with the abundance. Then, LASSO regression models were constructed by selecting the genes in the module that is most relevant to immune cells. Two test dataset was used to testify the model, and we finally, obtained a seven-genes survival model that performed an excellent prognostic efficacy.

Conclusion

In the current study, we filtered seven key genes that may be potential prognostic biomarkers of ESCC, and they may be used as new factors to improve the prognosis of cancer.

[Expression of melanoma-associated antigen-C2 in breast cancers and mechanism]

Objective: To analyze the expression pattern, mechanism and clinical significance of melanoma-associated antigen-C2 (MAGE-C2) in tumor-free breast specimens, breast benign disease specimens and breast cancer specimens. Methods: Reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry were used to investigate the expressions of MAGE-C2 in 60 tumor-free breast specimens, 60 breast benign disease specimens and 60 breast cancer specimens. The correlation of MAGE-C2 expression with clinicopathological parameters and prognosis of breast cancer patients were analyzed. The expression of MAGE-C2 was also detected by RT-PCR in breast cancer cell MCF-7 and MDA-MB-231 treated with DNA methylase inhibitor 5-aza-2'-deoxycytidine (5-aza-CdR) and histone deacetylase inhibitor trichostatin A (TSA). Results: The positive expression rates of MAGE-C2 mRNA and protein were 61.7% (37/60) and 58.3% (35/60) in breast cancer specimens, respectively, while negative expressed in breast and begin disease specimens. MAGE-C2 protein expression was associated with tumor grade, histological type and blood vessel invasion of breast cancer patients (P<0.05). The incidence of recurrence-free survival of patients with positive MAGE-C2 expression were lower than that of patients with negative MAGE-C2 expression (P<0.05). Multivariate Cox regression analysis showed that the clinical stage (P<0.01), lymph node metastasis (P<0.05) and MAGE-C2 expression (P<0.05) were the independent prognostic factors of breast cancer patients. The MAGE-C2 mRNA was not observed in the control and TSA treated breast cancer cells while upregulated in the 5-aza-CdR treated cells. Besides, 5-aza-CdR combined with TSA further enhanced MAGE-C2 mRNA level in breast cancer cells (P<0.05). Conclusions: MAGE-C2 is one of the tumor-specific antigen and its expression is related with the poor prognosis of breast cancer patients. DNA methylation and histone acetylation may be an important regulation mechanism of MAGE-C2 gene expression.

[Evidence summary for safety sleep protection strategy in infants]

Objective: To systematically review and summarize the relevant evidence of safe sleep protection strategies for infants at home and abroad, to provide a reference for clinical evidence-based decision-making and guideline formulation. Methods: "Infant Death/Sudden Unexpected Infant Death/Sudden Infant Death Syndrome" and "Sleep protecting program/Sleep safety/Sleeping environment" were used as search keywords. The literature retrieval for all the Chinese and English evidence on safe sleep protection strategies for infants published before March 2020 was conducted by using the National Guideline Clearinghouse (NGC), Registered Nurse' Association of Ontario (RNAO), National Institute for Health and Clinical Excellence (NICE), Scottish Intercollegiate Guidelines Network (SIGN), Guidelines International Network (GIN), JBI, Clinical Evidence, China Evidence-based Medicine Center, PubMed, Embase, CINAHL, Wanfang Data, CNKI and other databases. Inclusion criteria were guidelines, evidence summary and systematic reviews on infant safe sleep protection strategies for infants aged 0 to 1 years. The full text was available. Exclusion criteria include duplicates, directly translated documents as well as guide abstracts, discussion drafts, draft guides, interpretations, excerpts. The Appraisal of Guideline for research & Evaluation Instrument (AGREE Ⅱ) and A Measure Tool to Assess Systematic Reviews (AMSTAR 2) were used to compare and evaluate the selected literature, and extracted evidence from the literature that meets the quality standards. Results: A total of 12 articles were incorporated into study, including 1 Summary of evidence from UptoDate, 3 guidelines, and 8 systematic reviews. The results of the AGREE II quality evaluation showed that the overall quality of 3 guidelines was high. Among them, there was 1 with a recommendation level of "A", and 2 with a rating of "B". The AMSTAR 2 quality evaluation showed that the contents of the systematic reviews were relatively complete except for one literature. In the end, totally 39 terms of evidences were summarized, including 6 aspects of assessment, planning, implementation, health education (pregnant women, parents and other infant caregivers), evaluation, organization and policy. Conclusion: The evidence summary of infant safe sleep protection provides evidence support for formulating infant safe sleep care standards and carrying out scientific and high-quality clinical nursing practices.

[Prevalence of Spirometra mansoni infections in hosts in Jiangsu Province]

OBJECTIVE

To investigate the prevalence of Spirometra mansoni infections in hosts in Jiangsu Province, so as to provide the scientific basis for the management of sparganosis mansoni.

METHODS

From 2018 to 2019, nine counties (cities, districts) were randomly selected from Jiangsu Province as the survey sites, and 100 healthy individuals were randomly selected to perform the serological test of S. mansoni infections and the detection of S. mansoni eggs. The procercoids were detected in the intermediate host Cyclops, and the S. mansoni eggs were identified in the stool samples of the definitive hosts cats and dogs.

RESULTS

The prevalence of S. mansoni human infections was 0 (0/900) in the 9 survey sites of Jiangsu Province, and the sero-prevalence of the specific IgG antibody against S. mansoni was 1.22% (11/900). The positive rate of procercoids was 0.33% (3/900) in Cyclops. In addition, the S. mansoni egg-positive rate was 1.48% (2/135) in cats and dogs.

CONCLUSIONS

Sparganosis mansoni is prevalent in Jiangsu Province. Health education pertaining to the damages of sparganosis mansoni and the route of S. mansoni infections should be improved.

[Clinical observation of three-dimensional printing donor tooth model in peri-operative period of autotransplantation of tooth]

Objective: To prepare a three-dimensional (3D) printing donor tooth model and to observe its application in the peri-operative period. Methods: In part one, 192 cases (2017.9-2019.8) from Department of Oral & Maxillofacial Surgery, School of Stomatology, The Fourth Military Medical University ［107 males and 85 females, age (34.2±10.7) years］ which need autotransplantation of teeth (ATT) were collected. Whether the donor teeth can be completely extracted was predicted through clinical and imaging examination (first prediction). The second prediction was supplemented by the three-dimensional printing model of the donor teeth. Each of the prediction was compared with the actual results and the coincidence rate was calculated. In part two, 64 cases (2017.9-2019.8) from Department of Oral & Maxillofacial Surgery, School of Stomatology, The Fourth Military Medical University ［28 males, 36 females, age (30.2±8.3) years］ which need ATT were randomly divided into the model group and the donor group. The time of alveolar fossa preparation, time of donor tooth in vitro, times of trial implantation and time of pulptomy and root canal location were recorded respectively. Results: In part one, the coincidence rate between the second prediction and the actual results ［97.4%(187/192)］ was significantly higher than that of the first prediction ［93.2%(179/192)］ (P<0.05). In part two, the preparation time of the alveolar fossa in the maxillary and mandibular were (18.8±4.6) and (22.7±3.4) min, the time of the teeth in vitro were (3.0±0.6) and (2.1±0.6) min, the times of trial implantation were (1.3±0.8) and (1.0±0.9), and the time of pulpotomy and root canal location were (4.3±0.6) and (4.0±0.5) min. All values in the model groups were better than those in the donor group (P<0.05). Conclusions: The 3D printing model is accurate. It can be used in autogenous tooth transplantation to shorten the preparation time of alveolar fossa and time of donor tooth in vitro, and reduce the times of trial implantation of donor teeth, and to help to improve the prediction accuracy of complete extraction of donor teeth and the time of pulpotomy and root canal location.

The role of extracellular vesicles from stored RBC units in B lymphocyte survival and plasma cell differentiation

Extracellular vesicles (EVs) are small, double-membrane vesicles derived from erythrocytes, leukocytes, platelets, and cells of multiple tissues under physiologic or pathologic conditions. The role of EVs in stored RBC units is of great interest with respect to transfusion-related immunomodulation. The current study focuses on the quantity of EVs isolated from stored RBC units and their action on B cell-mediated immune responses. The in vitro experiment demonstrated that EVs exhibited a negative role in B cell survival, plasmacytic differentiation, and class switch recombination under LPS stimulation. Furthermore, LPS-induced antibody production was significantly decreased after EVs injection in vivo. Biochemical analysis revealed that EVs hampered the expression of Blimp-1 and IRF4 and the activation of NF-κB pathway in LPS-primed B cells. Overall, these data imply a vital role for EVs isolated from RBC units in B cell-mediated immune responses.

A five-microRNA signature for individualized prognosis evaluation and radiotherapy guidance in patients with diffuse lower-grade glioma

Despite the prognostic value of IDH and other gene mutations found in diffuse glioma, markers that judge individual prognosis of patients with diffuse lower‐grade glioma (LGG) are still lacking. This study aims to develop an expression‐based microRNA signature to provide survival and radiotherapeutic response prediction for LGG patients. MicroRNA expression profiles and relevant clinical information of LGG patients were downloaded from The Cancer Genome Atlas (TCGA; the training group) and the Chinese Glioma Genome Atlas (CGGA; the test group). Cox regression analysis, random survival forests‐variable hunting (RSFVH) screening and receiver operating characteristic (ROC) were used to identify the prognostic microRNA signature. ROC and TimeROC curves were plotted to compare the predictive ability of IDH mutation and the signature. Stratification analysis was conducted in patients with radiotherapy information. Gene ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed to explore the biological function of the signature. We identified a five‐microRNA signature that can classify patients into low‐risk or high‐risk group with significantly different survival in the training and test datasets (P < 0.001). The five‐microRNA signature was proved to be superior to IDH mutation in survival prediction (AUCtraining = 0.688 vs 0.607). Stratification analysis found the signature could further divide patients after radiotherapy into two risk groups. GO and KEGG analyses revealed that microRNAs from the prognostic signature were mainly enriched in cancer‐associated pathways. The newly discovered five‐microRNA signature could predict survival and radiotherapeutic response of LGG patients based on individual microRNA expression.

Effects of wet atmospheric nitrogen deposition on epiphytic lichens in the subtropical forests of Central China: Evaluation of the lichen food supply and quality of two endangered primates

Over the last few decades, the threat posed to biodiversity and ecosystem function by atmospheric nitrogen (N) deposition has been increasingly recognized. The disturbed nutrient balance and species composition of plants induced by higher N deposition can impact the biodiversity of the organisms that consume the plants. In this research, we implemented several experiments to estimate the effects of increased N deposition on the growth, survival, and nutrients of the dominant epiphytic lichens in the subtropical mountains in Central China to assess the lichen food amount and nutritional quality for two endangered primates endemic to China. Our results indicated that the thallus growth and propagule survival of the lichens were significantly decreased when nitrogen addition changed from 6.25 to 50.0 kg N·ha^-1·y^-1; it was also shown that lichen biomass could be decreased by 11.2%-70.2% when the deposition addition exceeded 6.25 kg N·ha^-1·y^-1. Further, our study revealed that increased nitrogen deposition also reduced the nutritional quality of the lichens via reducing the soluble protein and soluble sugar levels and increasing the fiber content, which would substantially affect the diet selection of the plants consumers in the region, particularly the populations of the two lichen-eating endangered primate species, Rhinopithecus roxellana and R. bieti. Our experimental study suggested that the nitrogen pollution derived from anthropogenic activities could cause cascading effects for the whole forest ecosystem of Central China; thus, more studies about nitrogen deposition in this region are required.

Efficacy of albumin and compounded plasma for plasma exchange in acquired thrombotic thrombocytopenic purpura

INTRODUCTION

Thrombotic thrombocytopenic purpura (TTP) is a rare life-threatening thrombotic microangiopathy. Therapeutic plasma exchange (TPE) is the first-line treatment for TTP. In our institution, albumin plus plasma (fresh frozen plasma [FFP] and/or cryoprecipitate-reduced plasma [CRP]) has been used as replacement fluid since 2014. We aimed to evaluate the efficacy of albumin combined with plasma as TPE for TTP.

MATERIAL AND METHODS

We retrospectively evaluated 20 patients admitted to our institution due to an acute episode of TTP between January 1, 2014 and February 1, 2019. They were divided into two groups according to the replacement fluid protocols: (a) albumin plus FFP (1:1) and (b) albumin plus mixed plasma [ie, albumin and FFP with CRP (2:1:1)] groups. Data on patient characteristics, replacement parameters, outcome, and hemorrhage risk were collected and analyzed.

RESULTS

There were no significant differences in treatment outcomes between the two groups (P > .05). However, the albumin plus mixed plasma group tended to require fewer plasma exchanges (median, 4) and shorter time to response (median, 15 days) compared to albumin plus FFP group (median, 6; 31 days). Although the cumulative survival of the albumin plus mixed plasma group was higher than the other group starting from day 23 after treatment, we did not observe significant difference (P = .50). No significant increase in the risk for hemorrhage was observed in either group.

CONCLUSIONS

The therapeutic efficacy of albumin and mixed plasma (2:1:1) is not inferior to that of albumin and FFP (1:1), and it can be used in treating TTP.

The Association Between Leucine and Diabetic Nephropathy in Different Gender: A Cross-Sectional Study in Chinese Patients With Type 2 Diabetes

OBJECTIVE

This study aimed to evaluate how leucine are associated with diabetic nephropathy (DN) in type 2 diabetes (T2D) patients and the gender difference of this association.

METHODS

We retrieved 1,031 consecutive patients with T2D who meet the inclusion and exclusion criteria from the same tertiary care center and extracted clinical information from electronic medical record. Plasma leucine was measured by liquid chromatography-mass spectrometer. Restricted cubic spline (RCS) was conducted to examine potential non-linear relationship between leucine and the risk of DN. Logistic regression was used to obtain odds ratio (OR) and confidence interval (CI). Additive interaction was used to estimate the interaction effect between leucine and gender for DN.

RESULTS

We found there was a negative correlation between leucine and the risk of DN. After stratifying all patients by gender, this relationship only remained significant in women (OR:0.57, CI:0.41-0.79).

CONCLUSIONS

In conclusion, T2D patients with high levels of leucine have a lower risk of developing DN in female.