Displaying publications 81 - 100 of 231 in total

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  1. Vermunt J, Bragg F, Halsey J, Yang L, Chen Y, Guo Y, et al.
    PMID: 34728472 DOI: 10.1136/bmjdrc-2021-002495
    INTRODUCTION: We examined the associations between long-term usual random plasma glucose (RPG) levels and cause-specific mortality risks among adults without known diabetes in China.

    RESEARCH DESIGN AND METHODS: The China Kadoorie Biobank recruited 512,891 adults (59% women) aged 30-79 from 10 regions of China during 2004-2008. At baseline survey, and subsequent resurveys of a random subset of survivors, participants were interviewed and measurements collected, including on-site RPG testing. Cause of death was ascertained via linkage to local mortality registries. Cox regression yielded adjusted HR for all-cause and cause-specific mortality associated with usual levels of RPG.

    RESULTS: During median 11 years' follow-up, 37,214 deaths occurred among 452,993 participants without prior diagnosed diabetes or other chronic diseases. There were positive log-linear relationships between RPG and all-cause, cardiovascular disease (CVD) (n=14,209) and chronic kidney disease (CKD) (n=432) mortality down to usual RPG levels of at least 5.1 mmol/L. At RPG <11.1 mmol/L, each 1.0 mmol/L higher usual RPG was associated with adjusted HRs of 1.14 (95% CI 1.12 to 1.16), 1.16 (1.12 to 1.19) and 1.44 (1.22 to 1.70) for all-cause, CVD and CKD mortality, respectively. Usual RPG was positively associated with chronic liver disease (n=547; 1.45 (1.26 to 1.66)) and cancer (n=12,680; 1.12 (1.09 to 1.16)) mortality, but with comparably lower risks at baseline RPG ≥11.1 mmol/L. These associations persisted after excluding participants who developed diabetes during follow-up.

    CONCLUSIONS: Among Chinese adults without diabetes, higher RPG levels were associated with higher mortality risks from several major diseases, with no evidence of apparent thresholds below the cut-points for diabetes diagnosis.

  2. Akhtar Z, Gallagher MM, Yap YG, Leung LWM, Elbatran AI, Madden B, et al.
    Pacing Clin Electrophysiol, 2021 05;44(5):875-882.
    PMID: 33792080 DOI: 10.1111/pace.14232
    BACKGROUND: Coronavirus disease-2019 (COVID-19) causes severe illness and multi-organ dysfunction. An abnormal electrocardiogram is associated with poor outcome, and QT prolongation during the illness has been linked to pharmacological effects. This study sought to investigate the effects of the COVID-19 illness on the corrected QT interval (QTc).

    METHOD: For 293 consecutive patients admitted to our hospital via the emergency department for COVID-19 between 01/03/20 -18/05/20, demographic data, laboratory findings, admission electrocardiograph and clinical observations were compared in those who survived and those who died within 6 weeks. Hospital records were reviewed for prior electrocardiograms for comparison with those recorded on presentation with COVID-19.

    RESULTS: Patients who died were older than survivors (82 vs 69.8 years, p 455 ms (males) and >465 ms (females) (p = 0.028, HR 1.49 [1.04-2.13]), as predictors of mortality. QTc prolongation beyond these dichotomy limits was associated with increased mortality risk (p = 0.0027, HR 1.78 [1.2-2.6]).

    CONCLUSION: QTc prolongation occurs in COVID-19 illness and is associated with poor outcome.

  3. Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, Damanakis K, et al.
    Phys Rev Lett, 2023 Dec 29;131(26):262301.
    PMID: 38215362 DOI: 10.1103/PhysRevLett.131.262301
    Quasireal photons exchanged in relativistic heavy ion interactions are powerful probes of the gluonic structure of nuclei. The coherent J/ψ photoproduction cross section in ultraperipheral lead-lead collisions is measured as a function of photon-nucleus center-of-mass energies per nucleon (W_{γN}^{Pb}) over a wide range of 40
  4. Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, Damanakis K, et al.
    Phys Rev Lett, 2023 Jul 07;131(1):011803.
    PMID: 37478454 DOI: 10.1103/PhysRevLett.131.011803
    The first search exploiting the vector boson fusion process to probe heavy Majorana neutrinos and the Weinberg operator at the LHC is presented. The search is performed in the same-sign dimuon final state using a proton-proton collision dataset recorded at sqrt[s]=13  TeV, collected with the CMS detector and corresponding to a total integrated luminosity of 138  fb^{-1}. The results are found to agree with the predictions of the standard model. For heavy Majorana neutrinos, constraints on the squared mixing element between the muon and the heavy neutrino are derived in the heavy neutrino mass range 50 GeV-25 TeV; for masses above 650 GeV these are the most stringent constraints from searches at the LHC to date. A first test of the Weinberg operator at colliders provides an observed upper limit at 95% confidence level on the effective μμ Majorana neutrino mass of 10.8 GeV.
  5. Sirunyan AM, Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, et al.
    Eur Phys J C Part Fields, 2021;81(9):800.
    PMID: 34781320 DOI: 10.1140/epjc/s10052-021-09538-2
    The measurement of the luminosity recorded by the CMS detector installed at LHC interaction point 5, using proton-proton collisions at s = 13 TeV in 2015 and 2016, is reported. The absolute luminosity scale is measured for individual bunch crossings using beam-separation scans (the van der Meer method), with a relative precision of 1.3 and 1.0% in 2015 and 2016, respectively. The dominant sources of uncertainty are related to residual differences between the measured beam positions and the ones provided by the operational settings of the LHC magnets, the factorizability of the proton bunch spatial density functions in the coordinates transverse to the beam direction, and the modeling of the effect of electromagnetic interactions among protons in the colliding bunches. When applying the van der Meer calibration to the entire run periods, the integrated luminosities when CMS was fully operational are 2.27 and 36.3 fb - 1 in 2015 and 2016, with a relative precision of 1.6 and 1.2%, respectively. These are among the most precise luminosity measurements at bunched-beam hadron colliders.
  6. Cui Y, Hada K, Kawashima T, Kino M, Lin W, Mizuno Y, et al.
    Nature, 2023 Sep;621(7980):711-715.
    PMID: 37758892 DOI: 10.1038/s41586-023-06479-6
    The nearby radio galaxy M87 offers a unique opportunity to explore the connections between the central supermassive black hole and relativistic jets. Previous studies of the inner region of M87 revealed a wide opening angle for the jet originating near the black hole1-4. The Event Horizon Telescope resolved the central radio source and found an asymmetric ring structure consistent with expectations from general relativity5. With a baseline of 17 years of observations, there was a shift in the jet's transverse position, possibly arising from an 8- to 10-year quasi-periodicity3. However, the origin of this sideways shift remains unclear. Here we report an analysis of radio observations over 22 years that suggests a period of about 11 years for the variation in the position angle of the jet. We infer that we are seeing a spinning black hole that induces the Lense-Thirring precession of a misaligned accretion disk. Similar jet precession may commonly occur in other active galactic nuclei but has been challenging to detect owing to the small magnitude and long period of the variation.
  7. Mullan KA, Anderson A, Shi YW, Ding JH, Ng CC, Chen Z, et al.
    Epilepsia, 2022 Feb 16.
    PMID: 35170024 DOI: 10.1111/epi.17182
    OBJECTIVE: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are severe cutaneous adverse drug reactions. Antiseizure medications (ASMs) with aromatic ring structure, including carbamazepine, are among the most common culprits. Screening for human leukocyte antigen (HLA) allele HLA-B*15:02 is recommended prior to initiating treatment with carbamazepine in Asians, but this allele has low positive predictive value.

    METHODS: We performed whole genome sequencing and analyzed 6 199 696 common variants among 113 aromatic ASM-induced SJS/TEN cases and 84 tolerant controls of Han Chinese ethnicity.

    RESULTS: In the primary analysis, nine variants reached genome-wide significance (p 

  8. Wu M, Li M, Yuan J, Liang S, Chen Z, Ye M, et al.
    Pharmacol Res, 2020 05;155:104693.
    PMID: 32057896 DOI: 10.1016/j.phrs.2020.104693
    Hormone therapy continues to be a favourable option in the management of menopausal symptomatology, but the associated risk-benefit ratios with respect to neurodegenerative diseases remain controversial. The study aim was to determine the relation between menopausal hormone therapy and Alzheimer's disease, dementia, and Parkinson's disease in human subjects. A literature search was performed in PubMed/Medline, Cochrane collaboration, and Scopus databases from onset of the database to September 2019. Random-effects model was used to estimate pooled odd ratio (OR) and 95 % confidence intervals (CI). Subgroup analysis was performed based on the type and formulation of hormone. In addition, the time-response effect of this relationship was also assessed based on duration of hormone therapy. Associations between hormone therapy and Alzheimer's disease, dementia, and Parkinson's disease in menopausal women were reported in 28 studies. Pooled results with random effect model showed a significant association between hormone therapy and Alzheimer's disease (OR 1.08, 95 % CI 1.03-1.14, I2: 69 %). This relationship was more pronounced in patients receiving the combined estrogen-progestogen formulation. Moreover, a significant non-linear time-response association between hormone therapy and Alzheimer's disease was also identified (Coef1 = 0.0477, p1<0.001; Coef2 = -0.0932, p2<0.001). Similarly, pooled analysis revealed a significant association between hormone therapy and all-cause dementia (OR 1.16, 95 % CI 1.02-1.31, I2: 19 %). Interestingly, no comparable relationship was uncovered between hormone therapy as a whole and Parkinson's disease (OR 1.14, 95 % CI 0.95-1.38, I2: 65 %); however, sub-group analysis revealed a significant relationship between the disease and progestogen (OR 3.41, 95 % CI 1.23-9.46) or combined estrogen-progestogen formulation use (OR 1.49, 95 % CI 1.34-1.65). Indeed, this association was also found to be driven by duration of exposure (Coef1 = 0.0626, p1 = 0.04). This study reveals a significant direct relationship between the use of certain hormonal therapies and Alzheimer's disease, all-cause dementia, and Parkinson's disease in menopausal women. However, the association appears to shift in direct after five years in the context of Alzheimer's disease, adding further weight to the critical window or timing hypothesis of neurodegeneration and neuroprotection.
  9. Ho WK, Tai MC, Dennis J, Shu X, Li J, Ho PJ, et al.
    Genet Med, 2022 Mar;24(3):586-600.
    PMID: 34906514 DOI: 10.1016/j.gim.2021.11.008
    PURPOSE: Non-European populations are under-represented in genetics studies, hindering clinical implementation of breast cancer polygenic risk scores (PRSs). We aimed to develop PRSs using the largest available studies of Asian ancestry and to assess the transferability of PRS across ethnic subgroups.

    METHODS: The development data set comprised 138,309 women from 17 case-control studies. PRSs were generated using a clumping and thresholding method, lasso penalized regression, an Empirical Bayes approach, a Bayesian polygenic prediction approach, or linear combinations of multiple PRSs. These PRSs were evaluated in 89,898 women from 3 prospective studies (1592 incident cases).

    RESULTS: The best performing PRS (genome-wide set of single-nucleotide variations [formerly single-nucleotide polymorphism]) had a hazard ratio per unit SD of 1.62 (95% CI = 1.46-1.80) and an area under the receiver operating curve of 0.635 (95% CI = 0.622-0.649). Combined Asian and European PRSs (333 single-nucleotide variations) had a hazard ratio per SD of 1.53 (95% CI = 1.37-1.71) and an area under the receiver operating curve of 0.621 (95% CI = 0.608-0.635). The distribution of the latter PRS was different across ethnic subgroups, confirming the importance of population-specific calibration for valid estimation of breast cancer risk.

    CONCLUSION: PRSs developed in this study, from association data from multiple ancestries, can enhance risk stratification for women of Asian ancestry.

  10. Jenkins TM, Jones SC, Lee CY, Forschler BT, Chen Z, Lopez-Martinez G, et al.
    Mol Phylogenet Evol, 2007 Mar;42(3):612-21.
    PMID: 17254806
    Coptotermes gestroi, the Asian subterranean termite (AST), is an economically important structural and agricultural pest that has become established in many areas of the world. For the first time, phylogeography was used to illuminate the origins of new found C. gestroi in the US Commonwealth of Puerto Rico; Ohio, USA; Florida, USA; and Brisbane, Australia. Phylogenetic relationships of C. gestroi collected in indigenous locations within Malaysia, Thailand, and Singapore as well as from the four areas of introduction were investigated using three genes (16S rRNA, COII, and ITS) under three optimality criteria encompassing phenetic and cladistic assumptions (maximum parsimony, maximum likelihood, and neighbor-joining). All three genes showed consistent support for a close genetic relationship between C. gestroi samples from Singapore and Ohio, whereas termite samples from Australia, Puerto Rico, and Key West, FL were more closely related to those from Malaysia. Shipping records further substantiated that Singapore and Malaysia were the likely origin of the Ohio and Australia C. gestroi, respectively. These data provide support for using phylogeography to understand the dispersal history of exotic termites. Serendipitously, we also gained insights into concerted evolution in an ITS cluster from rhinotermitid species in two genera.
  11. Chung HC, Kang YK, Chen Z, Bai Y, Wan Ishak WZ, Shim BY, et al.
    Cancer, 2022 Mar 01;128(5):995-1003.
    PMID: 34878659 DOI: 10.1002/cncr.34019
    BACKGROUND: KEYNOTE-063 (NCT03019588) investigated pembrolizumab versus paclitaxel as second-line therapy in Asian patients with advanced programmed death ligand 1 (PD-L1)-positive (combined positive score ≥1) gastric/gastroesophageal junction (GEJ) cancer.

    METHODS: This randomized, open-label, phase 3 study was conducted at 36 medical centers in China (mainland), Malaysia, South Korea, and Taiwan. Patients were randomly assigned 1:1 to 200 mg of pembrolizumab intravenously every 3 weeks for ≤2 years or 80 mg/m2 of paclitaxel intravenously every week. Primary end points were overall survival (OS) and progression-free survival (PFS). Secondary end points were objective response rate (ORR) per Response Evaluation Criteria in Solid Tumors version 1.1 and safety.

    RESULTS: Between February 16, 2017, and March 12, 2018, 94 patients were randomly assigned (47 pembrolizumab/47 paclitaxel) after screening; enrollment was stopped on March 12, 2018, based on the results of the global KEYNOTE-061 study, and patients were followed until the last patient's last visit. Median OS was 8 months (95% confidence interval [CI], 4-10 months) with pembrolizumab versus 8 months (95% CI, 5-11 months) with paclitaxel (hazard ratio [HR], 0.99; 95% CI, 0.63-1.54). Median PFS was 2 months (95% CI, 1-3 months) with pembrolizumab versus 4 months (95% CI, 3-6 months) with paclitaxel (HR, 1.62; 95% CI, 1.04-2.52). ORR was 13% for pembrolizumab versus 19% for paclitaxel. Any-grade treatment-related adverse events occurred in 28 pembrolizumab-treated patients (60%) and 42 paclitaxel-treated patients (96%); grades 3 to 5 events occurred in 5 patients (11%) and 28 patients (64%), respectively.

    CONCLUSIONS: Definitive conclusions about the efficacy of second-line pembrolizumab in Asian patients with advanced PD-L1-positive gastric/GEJ cancer are limited because of insufficient power, but pembrolizumab was well tolerated in this patient population. Efficacy followed a trend similar to that observed in the phase 3 KEYNOTE-061 trial.

  12. Qin S, Chen Z, Fang W, Ren Z, Xu R, Ryoo BY, et al.
    J Clin Oncol, 2023 Mar 01;41(7):1434-1443.
    PMID: 36455168 DOI: 10.1200/JCO.22.00620
    PURPOSE: We evaluated the efficacy and safety of pembrolizumab in patients from Asia with previously treated advanced hepatocellular carcinoma (HCC).

    METHODS: In a double-blind, phase III trial, 453 patients with advanced HCC and progression during or after treatment with or intolerance to sorafenib or oxaliplatin-based chemotherapy were randomly assigned in a 2:1 ratio to receive pembrolizumab (200 mg) or placebo once every 3 weeks for ≤ 35 cycles plus best supportive care. The primary end point was overall survival (one-sided significance threshold, P = .0193 [final analysis]). Secondary end points included progression-free survival (PFS) and objective response rate (ORR; one-sided significance threshold, P = .0134 and .0091, respectively [second interim analysis]; RECIST version 1.1, by blinded independent central review).

    RESULTS: Median overall survival was longer in the pembrolizumab group than in the placebo group (14.6 v 13.0 months; hazard ratio for death, 0.79; 95% CI, 0.63 to 0.99; P = .0180). Median PFS was also longer in the pembrolizumab group than in the placebo group (2.6 v 2.3 months; hazard ratio for progression or death, 0.74; 95% CI, 0.60 to 0.92; P = .0032). ORR was greater in the pembrolizumab group (12.7% [95% CI, 9.1 to 17.0]) than in the placebo group (1.3% [95% CI, 0.2 to 4.6]; P < .0001). Treatment-related adverse events occurred in 66.9% of patients (grade 3, 12.0%; grade 4, 1.3%; grade 5, 1.0%) in the pembrolizumab group and 49.7% of patients (grade 3, 5.9%; grade 4, 0%; grade 5, 0%) in the placebo group.

    CONCLUSION: In patients from Asia with previously treated advanced HCC, pembrolizumab significantly prolonged overall survival and PFS, and ORR was greater versus placebo.

  13. Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, Damanakis K, et al.
    Phys Rev Lett, 2023 Oct 13;131(15):151803.
    PMID: 37897747 DOI: 10.1103/PhysRevLett.131.151803
    We present an observation of photon-photon production of τ lepton pairs in ultraperipheral lead-lead collisions. The measurement is based on a data sample with an integrated luminosity of 404  μb^{-1} collected by the CMS experiment at a center-of-mass energy per nucleon pair of sqrt[s_{NN}]=5.02  TeV. The γγ→τ^{+}τ^{-} process is observed for τ^{+}τ^{-} events with a muon and three charged hadrons in the final state. The measured fiducial cross section is σ(γγ→τ^{+}τ^{-})=4.8±0.6(stat)±0.5(syst)  μb, where the second (third) term corresponds to the statistical (systematic) uncertainty in σ(γγ→τ^{+}τ^{-}) in agreement with leading-order QED predictions. Using σ(γγ→τ^{+}τ^{-}), we estimate a model-dependent value of the anomalous magnetic moment of the τ lepton of a_{τ}=0.001_{-0.089}^{+0.055}.
  14. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2018 Jun 08;120(23):231801.
    PMID: 29932697 DOI: 10.1103/PhysRevLett.120.231801
    The observation of Higgs boson production in association with a top quark-antiquark pair is reported, based on a combined analysis of proton-proton collision data at center-of-mass energies of sqrt[s]=7, 8, and 13 TeV, corresponding to integrated luminosities of up to 5.1, 19.7, and 35.9  fb^{-1}, respectively. The data were collected with the CMS detector at the CERN LHC. The results of statistically independent searches for Higgs bosons produced in conjunction with a top quark-antiquark pair and decaying to pairs of W bosons, Z bosons, photons, τ leptons, or bottom quark jets are combined to maximize sensitivity. An excess of events is observed, with a significance of 5.2 standard deviations, over the expectation from the background-only hypothesis. The corresponding expected significance from the standard model for a Higgs boson mass of 125.09 GeV is 4.2 standard deviations. The combined best fit signal strength normalized to the standard model prediction is 1.26_{-0.26}^{+0.31}.
  15. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2018 Aug 31;121(9):092002.
    PMID: 30230889 DOI: 10.1103/PhysRevLett.121.092002
    The χ_{b1}(3P) and χ_{b2}(3P) states are observed through their ϒ(3S)γ decays, using an event sample of proton-proton collisions collected by the CMS experiment at the CERN LHC. The data were collected at a center-of-mass energy of 13 TeV and correspond to an integrated luminosity of 80.0  fb^{-1}. The ϒ(3S) mesons are identified through their dimuon decay channel, while the low-energy photons are detected after converting to e^{+}e^{-} pairs in the silicon tracker, leading to a χ_{b}(3P) mass resolution of 2.2 MeV. This is the first time that the J=1 and 2 states are well resolved and their masses individually measured: 10513.42±0.41(stat)±0.18(syst)  MeV and 10524.02±0.57(stat)±0.18(syst)  MeV; they are determined with respect to the world-average value of the ϒ(3S) mass, which has an uncertainty of 0.5 MeV. The mass splitting is measured to be 10.60±0.64(stat)±0.17(syst)  MeV.
  16. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2018 Oct 05;121(14):141801.
    PMID: 30339440 DOI: 10.1103/PhysRevLett.121.141801
    This Letter presents the observation of the rare Z boson decay Z→ψℓ^{+}ℓ^{-}. Here, ψ represents contributions from direct J/ψ and ψ(2S)→J/ψX, ℓ^{+}ℓ^{-} is a pair of electrons or muons, and the J/ψ meson is detected via its decay to μ^{+}μ^{-}. The sample of proton-proton collision data, collected by the CMS experiment at the LHC at a center-of-mass energy of 13 TeV, corresponds to an integrated luminosity of 35.9  fb^{-1}. The signal is observed with a significance in excess of 5 standard deviations. After subtraction of the ψ(2S)→J/ψX contribution, the ratio of the branching fraction of the exclusive decay Z→J/ψℓ^{+}ℓ^{-} to the decay Z→μ^{+}μ^{-}μ^{+}μ^{-} within a fiducial phase space is measured to be B(Z→J/ψℓ^{+}ℓ^{-})/B(Z→μ^{+}μ^{-}μ^{+}μ^{-})=0.67±0.18(stat)±0.05(syst).
  17. Hayrapetyan A, Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, et al.
    Phys Rev Lett, 2023 Sep 01;131(9):091903.
    PMID: 37721839 DOI: 10.1103/PhysRevLett.131.091903
    A search for the rare η→μ^{+}μ^{-}μ^{+}μ^{-} double-Dalitz decay is performed using a sample of proton-proton collisions, collected by the CMS experiment at the CERN LHC with high-rate muon triggers during 2017 and 2018 and corresponding to an integrated luminosity of 101  fb^{-1}. A signal having a statistical significance well in excess of 5 standard deviations is observed. Using the η→μ^{+}μ^{-} decay as normalization, the branching fraction B(η→μ^{+}μ^{-}μ^{+}μ^{-})=[5.0±0.8(stat)±0.7(syst)±0.7(B_{2μ})]×10^{-9} is measured, where the last term is the uncertainty in the normalization channel branching fraction. This work achieves an improved precision of over 5 orders of magnitude compared to previous results, leading to the first measurement of this branching fraction, which is found to agree with theoretical predictions.
  18. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, et al.
    Phys Rev Lett, 2020 Oct 09;125(15):151802.
    PMID: 33095594 DOI: 10.1103/PhysRevLett.125.151802
    The first observation is reported of the combined production of three massive gauge bosons (VVV with V=W, Z) in proton-proton collisions at a center-of-mass energy of 13 TeV. The analysis is based on a data sample recorded by the CMS experiment at the CERN LHC corresponding to an integrated luminosity of 137  fb^{-1}. The searches for individual WWW, WWZ, WZZ, and ZZZ production are performed in final states with three, four, five, and six leptons (electrons or muons), or with two same-sign leptons plus one or two jets. The observed (expected) significance of the combined VVV production signal is 5.7 (5.9) standard deviations and the corresponding measured cross section relative to the standard model prediction is 1.02_{-0.23}^{+0.26}. The significances of the individual WWW and WWZ production are 3.3 and 3.4 standard deviations, respectively. Measured production cross sections for the individual triboson processes are also reported.
  19. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, et al.
    Phys Rev Lett, 2020 Oct 09;125(15):152001.
    PMID: 33095627 DOI: 10.1103/PhysRevLett.125.152001
    Using a data sample of proton-proton collisions at sqrt[s]=13  TeV, corresponding to an integrated luminosity of 140  fb^{-1} collected by the CMS experiment in 2016-2018, the B_{s}^{0}→X(3872)ϕ decay is observed. Decays into J/ψπ^{+}π^{-} and K^{+}K^{-} are used to reconstruct, respectively, the X(3872) and ϕ. The ratio of the product of branching fractions B[B_{s}^{0}→X(3872)ϕ]B[X(3872)→J/ψπ^{+}π^{-}] to the product B[B_{s}^{0}→ψ(2S)ϕ]B[ψ(2S)→J/ψπ^{+}π^{-}] is measured to be [2.21±0.29(stat)±0.17(syst)]%. The ratio B[B_{s}^{0}→X(3872)ϕ]/B[B^{0}→X(3872)K^{0}] is found to be consistent with one, while the ratio B[B_{s}^{0}→X(3872)ϕ]/B[B^{+}→X(3872)K^{+}] is two times smaller. This suggests a difference in the production dynamics of the X(3872) in B^{0} and B_{s}^{0} meson decays compared to B^{+}. The reported observation may shed new light on the nature of the X(3872) particle.
  20. Sirunyan AM, Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, et al.
    Phys Rev Lett, 2021 Jun 25;126(25):252003.
    PMID: 34241504 DOI: 10.1103/PhysRevLett.126.252003
    The Ξ_{b}^{-}π^{+}π^{-} invariant mass spectrum is investigated with an event sample of proton-proton collisions at sqrt[s]=13  TeV, collected by the CMS experiment at the LHC in 2016-2018 and corresponding to an integrated luminosity of 140  fb^{-1}. The ground state Ξ_{b}^{-} is reconstructed via its decays to J/ψΞ^{-} and J/ψΛK^{-}. A narrow resonance, labeled Ξ_{b}(6100)^{-}, is observed at a Ξ_{b}^{-}π^{+}π^{-} invariant mass of 6100.3±0.2(stat)±0.1(syst)±0.6(Ξ_{b}^{-})  MeV, where the last uncertainty reflects the precision of the Ξ_{b}^{-} baryon mass. The upper limit on the Ξ_{b}(6100)^{-} natural width is determined to be 1.9  MeV at 95% confidence level. The low Ξ_{b}(6100)^{-} signal yield observed in data does not allow a measurement of the quantum numbers of the new state. However, following analogies with the established excited Ξ_{c} baryon states, the new Ξ_{b}(6100)^{-} resonance and its decay sequence are consistent with the orbitally excited Ξ_{b}^{-} baryon, with spin and parity quantum numbers J^{P}=3/2^{-}.
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