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1.
Phys Rev Lett ; 132(13): 131801, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38613276

RESUMEN

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.

3.
Zhonghua Jie He He Hu Xi Za Zhi ; 47(3): 214-221, 2024 Mar 12.
Artículo en Chino | MEDLINE | ID: mdl-38448170

RESUMEN

A 64-year-old female patient was admitted to Beijing Chao-Yang Hospital on February 21, 2023 because of right-sided chest pain for more than 4 years and left-sided chest pain for more than 9 months. She had a past medical history of previous tuberculosis and rheumatoid arthritis. A chest CT in October 2018 revealed multiple pulmonary nodules. A CT-guided biopsy showed no tumors, and adenosine deaminase levels in the pleural effusion were elevated, suggesting a high likelihood of tuberculosis. As a result, anti-tuberculosis treatment was initiated in March 2019. In December 2019, she underwent a right lower lobe resection due to localized hydropneumothorax on the right side. Postoperative pathology unveiled granulomatous inflammation with necrosis. A chest CT in May 2020 showed a significant increase in nodules and cavities. In January 2023, a diagnosis of cryptococcal pneumonia was considered, and she was prescribed oral fluconazole. Finally, the diagnosis of pulmonary rheumatoid nodules was confirmed after a pathological consultation of the postoperative specimen. After one month of treatment with oral prednisone and mycophenolate mofetil, a follow-up chest CT showed improvement. It was recommended that she continue with her current treatment and undergo regular chest CT scans.


Asunto(s)
Criptococosis , Nódulos Pulmonares Múltiples , Tuberculosis , Humanos , Femenino , Persona de Mediana Edad , Dolor en el Pecho , Criptococosis/diagnóstico , Hospitalización
4.
Phys Rev Lett ; 132(8): 081901, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38457697

RESUMEN

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.

5.
Phys Rev Lett ; 132(8): 081802, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38457722

RESUMEN

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.

6.
Phys Rev Lett ; 132(5): 051802, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38364143

RESUMEN

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.

7.
Phys Rev Lett ; 132(2): 021801, 2024 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-38277604

RESUMEN

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 ß 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.

8.
Phys Rev Lett ; 131(17): 171901, 2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37955487

RESUMEN

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.

9.
Phys Rev Lett ; 131(17): 171802, 2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37955501

RESUMEN

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.

10.
J Womens Health (Larchmt) ; 32(12): 1351-1362, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37930683

RESUMEN

Purpose: The aim of this study was to utilize an intersectional framework to examine academic faculty's lived experiences during COVID-19. Specifically, we set out to: (1) describe the multiple intersectional identities (e.g., gender, race/ethnicity, rank, caregiver status, disability status) represented by the faculty, (2) examine potential disparities in well-being, workload, and productivity linked to these intersectional factors, and (3) identify qualitative themes endorsed by faculty as they relate to lived experiences during COVID-19. Methods: This was a cross-sectional mixed-methods research study. The Center for Women in Medicine and Science (CWIMS) at the University of Minnesota developed and implemented a survey between February-June of 2021 in response to national reports of disparities in the impacts of COVID-19 on faculty with lived experiences from multiple intersections. Results: There were 291 full-time faculty who participated in the study. Quantitative findings indicated that faculty with multiple intersectional identities (e.g., woman+assistant professor+caregiver+underrepresented in medicine) reported greater depression symptoms, work/family conflict, and stress in contrast to faculty with fewer intersectional identities. Furthermore, faculty with more intersectional identities reported higher clinical workloads and service responsibilities and lower productivity with regard to research article submissions, publications, and grant submissions in contrast to faculty with fewer intersectional identities. Qualitative findings supported quantitative findings and broadened understanding of potential underlying reasons. Conclusions: Findings confirm anecdotal evidence that faculty with lived experiences from multiple intersections may be disproportionately experiencing negative outcomes from the pandemic. These findings can inform decisions about how to address these disparities moving into the next several years with regard to promotion and tenure, burnout and well-being, and faculty retention in academic medical settings. Given these findings, it is also important to intentionally plan responses for future public health crises to prevent continued disparities for faculty with multiple intersectional identities.


Asunto(s)
COVID-19 , Marco Interseccional , Humanos , Femenino , Carga de Trabajo , Estudios Transversales , Pandemias , Docentes Médicos
11.
Phys Rev Lett ; 131(15): 151801, 2023 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-37897753

RESUMEN

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.

12.
Phys Rev Lett ; 131(13): 131902, 2023 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-37831985

RESUMEN

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.

13.
Phys Rev Lett ; 131(13): 131901, 2023 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-37832008

RESUMEN

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.

14.
Phys Rev Lett ; 131(10): 102301, 2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37739372

RESUMEN

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

15.
Phys Rev Lett ; 131(11): 111802, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37774262

RESUMEN

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.

16.
Front Public Health ; 11: 1221675, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37670825

RESUMEN

Introduction: Chronic non-communicable diseases (NCDs) are predominantly related to modifiable health behaviors and account for 74% of global deaths at present. Behavior modification through self-management is a strategy to prevent NCDs. Chronic Disease Self-Management Programs (CDSMPs) have demonstrated improvements in health behaviors, health status, and use of healthcare. Objective: We evaluated the effects of a 6-week CDSMP on self-efficacy, health behaviors, mental health, health-related quality of life (HR-QoL), and health responsibilities among vulnerable populations with chronic disease in Europe. Methods: A prospective cohort study with a 6-month pre-post single-group design was conducted in five European countries. The intervention targeted adults with chronic conditions and low socioeconomic status, as well as their caregivers. The intervention was a 6-week community-based CDSMP in a group setting. Outcomes were measured per self-report questionnaire at baseline and 6-month follow-up: self-efficacy, health behaviors, mental health, HR-QoL, and health responsibilities. Results: Of 1,844 participants, 1,248 (67.7%) completed follow-up and attended ≥4 sessions. For the chronic condition group, the following outcome measures at follow-up significantly improved compared with baseline (all P < 0.002): self-efficacy (SEMCD-6 6.7 vs. 6.4), mental health (PHQ-8 6.3 vs. 7.0), HR-QoL (SF-12 PCS 42.3 vs. 40.2, SF-12 MCS 42.8 vs. 41.4), health utility (EQ-5D-5L 0.88 vs. 0.86), self-rated health (EQ-5D-5L 67.2 vs. 63.9), communication with healthcare providers (2.28 vs. 2.11), understanding information (3.10 vs. 3.02), number of doctor visits (3.61 vs. 4.97), accident and emergency department visits (0.25 vs. 0.48), total nights in a hospital (0.65 vs. 1.13), and perceived medical errors (19.6 vs. 28.7%). No significant changes were detected in dietary habits, physical activity, substance use, and sleep and fatigue. For caregivers without a chronic condition, only doctor visits significantly decreased (1.54 vs. 2.25, P < 0.001). Discussion: This CDSMP was associated with improvement in self-efficacy, depression, HR-QoL, and health responsibilities over 6 months in a diverse European population with a chronic condition. However, additional interventions targeting lifestyle risk factors are needed to improve health outcomes.


Asunto(s)
Automanejo , Adulto , Humanos , Poblaciones Vulnerables , Calidad de Vida , Servicios de Salud Comunitaria , Estudios Prospectivos , Procesos de Grupo , Enfermedad Crónica
17.
Phys Rev Lett ; 131(9): 091901, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37721819

RESUMEN

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.

18.
Phys Rev Lett ; 131(9): 091802, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37721849

RESUMEN

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.

19.
Phys Rev Lett ; 131(7): 071901, 2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37656865

RESUMEN

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.

20.
Phys Rev Lett ; 131(3): 031901, 2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37540878

RESUMEN

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.

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