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Determination of Spin-Parity Quantum Numbers of X(2370) as 0^{-+} from J/ψ→γK_{S}^{0}K_{S}^{0}η^{'}. PHYSICAL REVIEW LETTERS 2024; 132:181901. [PMID: 38759175 DOI: 10.1103/physrevlett.132.181901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 03/05/2024] [Accepted: 03/28/2024] [Indexed: 05/19/2024]
Abstract
Based on (10087±44)×10^{6} J/ψ events collected with the BESIII detector, a partial wave analysis of the decay J/ψ→γK_{S}^{0}K_{S}^{0}η^{'} is performed. The mass and width of the X(2370) are measured to be 2395±11(stat)_{-94}^{+26}(syst) MeV/c^{2} and 188_{-17}^{+18}(stat)_{-33}^{+124}(syst) MeV, respectively. The corresponding product branching fraction is B[J/ψ→γX(2370)]×B[X(2370)→f_{0}(980)η^{'}]×B[f_{0}(980)→K_{S}^{0}K_{S}^{0}]=(1.31±0.22(stat)_{-0.84}^{+2.85}(syst))×10^{-5}. The statistical significance of the X(2370) is greater than 11.7σ and the spin parity is determined to be 0^{-+} for the first time. The measured mass and spin parity of the X(2370) are consistent with the predictions of the lightest pseudoscalar glueball.
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2
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Observation of Structures in the Processes e^{+}e^{-}→ωχ_{c1} and ωχ_{c2}. PHYSICAL REVIEW LETTERS 2024; 132:161901. [PMID: 38701481 DOI: 10.1103/physrevlett.132.161901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 03/13/2024] [Accepted: 03/22/2024] [Indexed: 05/05/2024]
Abstract
We present measurements of the Born cross sections for the processes e^{+}e^{-}→ωχ_{c1} and ωχ_{c2} at center-of-mass energies sqrt[s] from 4.308 to 4.951 GeV. The measurements are performed with data samples corresponding to an integrated luminosity of 11.0 fb^{-1} collected with the BESIII detector operating at the Beijing Electron Positron Collider storage ring. Assuming the e^{+}e^{-}→ωχ_{c2} signals come from a single resonance, the mass and width are determined to be M=(4413.6±9.0±0.8) MeV/c^{2} and Γ=(110.5±15.0±2.9) MeV, respectively, which is consistent with the parameters of the well-established resonance ψ(4415). In addition, we also use one single resonance to describe the e^{+}e^{-}→ωχ_{c1} line shape and determine the mass and width to be M=(4544.2±18.7±1.7) MeV/c^{2} and Γ=(116.1±33.5±1.7) MeV, respectively. The structure of this line shape, observed for the first time, requires further understanding.
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3
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Coupled-Channel Analysis of the χ_{c1}(3872) Line Shape with BESIII Data. PHYSICAL REVIEW LETTERS 2024; 132:151903. [PMID: 38682963 DOI: 10.1103/physrevlett.132.151903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 01/03/2024] [Accepted: 03/11/2024] [Indexed: 05/01/2024]
Abstract
We perform a study of the χ_{c1}(3872) line shape using the data samples of e^{+}e^{-}→γχ_{c1}(3872), χ_{c1}(3872)→D^{0}D[over ¯]^{0}π^{0}, and π^{+}π^{-}J/ψ collected with the BESIII detector. The effects of the coupled channels and the off-shell D^{*0} are included in the parametrization of the line shape. The line shape mass parameter is obtained to be M_{X}=(3871.63±0.13_{-0.05}^{+0.06}) MeV. Two poles are found on the first and second Riemann sheets corresponding to the D^{*0}D[over ¯]^{0} branch cut. The pole location on the first sheet is much closer to the D^{*0}D[over ¯]^{0} threshold than the other, and is determined to be 7.04±0.15_{-0.08}^{+0.07} MeV above the D^{0}D[over ¯]^{0}π^{0} threshold with an imaginary part -0.19±0.08_{-0.19}^{+0.14} MeV.
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4
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Observation of the Anomalous Shape of X(1840) in J/ψ→γ3(π^{+}π^{-}) Indicating a Second Resonance Near pp[over ¯] Threshold. PHYSICAL REVIEW LETTERS 2024; 132:151901. [PMID: 38682972 DOI: 10.1103/physrevlett.132.151901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 01/16/2024] [Accepted: 02/23/2024] [Indexed: 05/01/2024]
Abstract
Using a sample of (10087±44)×10^{6} J/ψ events, which is about 45 times larger than that was previously analyzed, a further investigation on the J/ψ→γ3(π^{+}π^{-}) decay is performed. A significant distortion at 1.84 GeV/c^{2} in the line shape of the 3(π^{+}π^{-}) invariant mass spectrum is observed for the first time, which could be resolved by two overlapping resonant structures, X(1840) and X(1880). The new state X(1880) is observed with a statistical significance larger than 10σ. The mass and width of X(1880) are determined to be 1882.1±1.7±0.7 MeV/c^{2} and 30.7±5.5±2.4 MeV, respectively, which indicates the existence of a pp[over ¯] bound state.
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5
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Study of the f_{0}(980) and f_{0}(500) Scalar Mesons through the Decay D_{s}^{+}→π^{+}π^{-}e^{+}ν_{e}. PHYSICAL REVIEW LETTERS 2024; 132:141901. [PMID: 38640399 DOI: 10.1103/physrevlett.132.141901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 11/29/2023] [Accepted: 02/28/2024] [Indexed: 04/21/2024]
Abstract
Using e^{+}e^{-} collision data corresponding to an integrated luminosity of 7.33 fb^{-1} recorded by the BESIII detector at center-of-mass energies between 4.128 and 4.226 GeV, we present an analysis of the decay D_{s}^{+}→π^{+}π^{-}e^{+}ν_{e}, where the D_{s}^{+} is produced via the process e^{+}e^{-}→D_{s}^{*±}D_{s}^{∓}. We observe the f_{0}(980) in the π^{+}π^{-} system and the branching fraction of the decay D_{s}^{+}→f_{0}(980)e^{+}ν_{e} with f_{0}(980)→π^{+}π^{-} measured to be (1.72±0.13_{stat}±0.10_{syst})×10^{-3}, where the uncertainties are statistical and systematic, respectively. The dynamics of the D_{s}^{+}→f_{0}(980)e^{+}ν_{e} decay are studied with the simple pole parametrization of the hadronic form factor and the Flatté formula describing the f_{0}(980) in the differential decay rate, and the product of the form factor f_{+}^{f_{0}}(0) and the c→s Cabibbo-Kobayashi-Maskawa matrix element |V_{cs}| is determined for the first time to be f_{+}^{f_{0}}(0)|V_{cs}|=0.504±0.017_{stat}±0.035_{syst}. Furthermore, the decay D_{s}^{+}→f_{0}(500)e^{+}ν_{e} is searched for the first time but no signal is found. The upper limit on the branching fraction of D_{s}^{+}→f_{0}(500)e^{+}ν_{e}, f_{0}(500)→π^{+}π^{-} decay is set to be 3.3×10^{-4} at 90% confidence level.
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6
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Observation of D^{+}→K_{S}^{0}a_{0}(980)^{+} in the Amplitude Analysis of D^{+}→K_{S}^{0}π^{+}η. PHYSICAL REVIEW LETTERS 2024; 132:131903. [PMID: 38613307 DOI: 10.1103/physrevlett.132.131903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Revised: 01/10/2024] [Accepted: 02/14/2024] [Indexed: 04/14/2024]
Abstract
We perform for the first time an amplitude analysis of the decay D^{+}→K_{S}^{0}π^{+}η and report the observation of the decay D^{+}→K_{S}^{0}a_{0}(980)^{+} using 2.93 fb^{-1} of e^{+}e^{-} collision data taken at a center-of-mass energy of 3.773 GeV with the BESIII detector. As the only W-annihilation-free decay among D to a_{0}(980) pseudoscalar, D^{+}→K_{S}^{0}a_{0}(980)^{+} is the ideal decay in extracting the contributions of the W-emission amplitudes involving a_{0}(980) and to study the final-state interactions. The absolute branching fraction of D^{+}→K_{S}^{0}π^{+}η is measured to be (1.27±0.04_{stat}±0.03_{syst})%. The branching fractions of intermediate processes D^{+}→K_{S}^{0}a_{0}(980)^{+} with a_{0}(980)^{+}→π^{+}η and D^{+}→π^{+}K[over ¯]_{0}^{*}(1430)^{0} with K[over ¯]_{0}^{*}(1430)^{0}→K_{S}^{0}η are measured to be (1.33±0.05_{stat}±0.04_{syst})% and (0.14±0.03_{stat}±0.01_{syst})%, respectively.
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7
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Observation of Significant Flavor-SU(3) Breaking in the Kaon Wave Function at 12<Q^{2}<25 GeV^{2} and Discovery of the Charmless Decay ψ(3770)→K_{S}^{0}K_{L}^{0}. PHYSICAL REVIEW LETTERS 2024; 132:131901. [PMID: 38613263 DOI: 10.1103/physrevlett.132.131901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 02/11/2024] [Accepted: 02/13/2024] [Indexed: 04/14/2024]
Abstract
We present cross sections for the reaction e^{+}e^{-}→K_{S}^{0}K_{L}^{0} at center-of-mass energies ranging from 3.51 to 4.95 GeV using data samples collected in the BESIII experiment, corresponding to a total integrated luminosity of 26.5 fb^{-1}. The ratio of neutral-to-charged kaon form factors at large momentum transfers (12
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8
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Investigation of the ΔI=1/2 Rule and Test of CP Symmetry through the Measurement of Decay Asymmetry Parameters in Ξ^{-} Decays. PHYSICAL REVIEW LETTERS 2024; 132:101801. [PMID: 38518329 DOI: 10.1103/physrevlett.132.101801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Accepted: 02/01/2024] [Indexed: 03/24/2024]
Abstract
Using (10087±44)×10^{6} J/ψ events collected with the BESIII detector, numerous Ξ^{-} and Λ decay asymmetry parameters are simultaneously determined from the process J/ψ→Ξ^{-}Ξ[over ¯]^{+}→Λ(pπ^{-})π^{-}Λ[over ¯](n[over ¯]π^{0})π^{+} and its charge-conjugate channel. The precisions of α_{Λ0} for Λ→nπ^{0} and α[over ¯]_{Λ0} for Λ[over ¯]→n[over ¯]π^{0} compared to world averages are improved by factors of 4 and 1.7, respectively. The ratio of decay asymmetry parameters of Λ→nπ^{0} to that of Λ→pπ^{-}, ⟨α_{Λ0}⟩/⟨α_{Λ-}⟩, is determined to be 0.873±0.012_{-0.010}^{+0.011}, where the first and the second uncertainties are statistical and systematic, respectively. The ratio is smaller than unity more than 5σ, which signifies the existence of the ΔI=3/2 transition in Λ for the first time. Besides, we test for CP symmetry in Ξ^{-}→Λπ^{-} and in Λ→nπ^{0} with the best precision to date.
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Observation of D_{s}^{+}→η^{'}μ^{+}ν_{μ}, Precision Test of Lepton Flavor Universality with D_{s}^{+}→η^{(')}l^{+}ν_{l}, and First Measurements of D_{s}^{+}→η^{(')}μ^{+}ν_{μ} Decay Dynamics. PHYSICAL REVIEW LETTERS 2024; 132:091802. [PMID: 38489649 DOI: 10.1103/physrevlett.132.091802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 01/25/2024] [Accepted: 01/26/2024] [Indexed: 03/17/2024]
Abstract
By analyzing 7.33 fb^{-1} of e^{+}e^{-} annihilation data collected at center-of-mass energies between 4.128 and 4.226 GeV with the BESIII detector, we report the observation of the semileptonic decay D_{s}^{+}→η^{'}μ^{+}ν_{μ}, with a statistical significance larger than 10σ, and the measurements of the D_{s}^{+}→ημ^{+}ν_{μ} and D_{s}^{+}→η^{'}μ^{+}ν_{μ} decay dynamics for the first time. The branching fractions of D_{s}^{+}→ημ^{+}ν_{μ} and D_{s}^{+}→η^{'}μ^{+}ν_{μ} are determined to be (2.235±0.051_{stat}±0.052_{syst})% and (0.801±0.055_{stat}±0.028_{syst})%, respectively, with precision improved by factors of 6.0 and 6.6 compared to the previous best measurements. Combined with the results for the decays D_{s}^{+}→ηe^{+}ν_{e} and D_{s}^{+}→η^{'}e^{+}ν_{e}, the ratios of the decay widths are examined both inclusively and in several ℓ^{+}ν_{ℓ} four-momentum transfer ranges. No evidence for lepton flavor universality violation is found within the current statistics. The products of the hadronic form factors f_{+,0}^{η^{(')}}(0) and the c→s Cabibbo-Kobayashi-Maskawa matrix element |V_{cs}| are determined. The results based on the two-parameter series expansion are f_{+,0}^{η}(0)|V_{cs}|=0.452±0.010_{stat}±0.007_{syst} and f_{+,0}^{η^{'}}(0)|V_{cs}|=0.504±0.037_{stat}±0.012_{syst}, which help to constrain present models on f_{+,0}^{η^{(')}}(0). The forward-backward asymmetries are determined to be ⟨A_{FB}^{η}⟩=-0.059±0.031_{stat}±0.005_{syst} and ⟨A_{FB}^{η^{'}}⟩=-0.064±0.079_{stat}±0.006_{syst} for the first time, which are consistent with the theoretical calculation.
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10
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Determination of the Σ^{+} Timelike Electromagnetic Form Factors. PHYSICAL REVIEW LETTERS 2024; 132:081904. [PMID: 38457707 DOI: 10.1103/physrevlett.132.081904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 11/24/2023] [Accepted: 01/12/2024] [Indexed: 03/10/2024]
Abstract
Based on data samples collected with the BESIII detector at the BEPCII collider, the process e^{+}e^{-}→Σ^{+}Σ[over ¯]^{-} is studied at center-of-mass energies sqrt[s]=2.3960, 2.6454, and 2.9000 GeV. Using a fully differential angular description of the final state particles, both the relative magnitude and phase information of the Σ^{+} electromagnetic form factors in the timelike region are extracted. The relative phase between the electric and magnetic form factors is determined to be sinΔΦ=-0.67±0.29(stat)±0.18(syst) at sqrt[s]=2.3960 GeV, ΔΦ=55°±19°(stat)±14°(syst) at sqrt[s]=2.6454 GeV, and 78°±22°(stat)±9°(syst) at sqrt[s]=2.9000 GeV. For the first time, the phase of the hyperon electromagnetic form factors is explored in a wide range of four-momentum transfer. The evolution of the phase along with four-momentum transfer is an important input for understanding its asymptotic behavior and the dynamics of baryons.
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11
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[The cases of tracing the source of patients infected with Omicron variant of SARS-CoV-2 based on wastewater-based epidemiology in Shenzhen]. ZHONGHUA YI XUE ZA ZHI 2024; 104:302-307. [PMID: 38246776 DOI: 10.3760/cma.j.cn112137-20231016-00766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/23/2024]
Abstract
Wastewater-based epidemiology (WBE) is an emerging discipline, which has been applied to drug abuse tracking and infectious disease pathogen surveillance. During the COVID-19 epidemic, WBE has been applied to monitor the epidemic trend and SARS-CoV-2 variants etc. In order to detect hidden COVID-19 cases and prevent transmission in the community, wastewater surveillance system for monitoring SARS-CoV-2 RNA was developed in Shenzhen. The sewage sampling sites were set up in key places such as the port areas, urban villages and residential communities of Futian, Nanshan, Luohu and Yantian districts. From July 26 to November 30, 2022, a total of 369 sewage sampling sites were set up, covering 1.93 million people. Continuous sampling was carried out for 3 hours in the peak period of water use every day. Sewage virus enrichment and SARS-CoV-2 nucleic acid detection were carried out by polyethylene glycol precipitation method and RT-qPCR, and a positive water sample disposal process was molded. This article aims to introduce the case of source tracing of COVID-19 infected patients based on urban sewage in Shenzhen. The sewage monitoring of Honghu water treatment plant in Luohu District played an early warning role, and the source of infection was traced. In the disposal of positive water samples in Futian South Road, Futian District, the important experience of monitoring point layout was obtained. In the sewage monitoring of Nanshan village, Nanshan District, the existence of occult infection was revealed. Sharing the experience of tracing the source of COVID-19 patients to avoid the spread of COVID-19 in the community based on wastewater surveillance of SARS-CoV-2 RNA in Shenzhen, and summarizing the advantages and application prospects of sewage surveillance can provide new ideas for monitoring emerging or re-emerging pathogens that are known to exhibit gastrointestinal excretion in the future.
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[5 cases of occupational heat illness]. ZHONGHUA LAO DONG WEI SHENG ZHI YE BING ZA ZHI = ZHONGHUA LAODONG WEISHENG ZHIYEBING ZAZHI = CHINESE JOURNAL OF INDUSTRIAL HYGIENE AND OCCUPATIONAL DISEASES 2024; 42:58-61. [PMID: 38311953 DOI: 10.3760/cma.j.cn121094-20211118-221574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/06/2024]
Abstract
Objective: Through the analysis of five cases of occupational heat illness caused by high temperature, we expounded the pathogenesis and summarized the clinical characteristics of heat cramp and heat exhaustion of the newly revised diagnostic criteria for occupational heat illness (GBZ41-2019), in order to prevent the occurrence of occupational heat illness to put forward controllable countermeasures. Methods: According to the occupational history, clinical diagnosis and treatment and the other relevant data submitted by five patients, the diagnosis process was analyzed and summarized. Results: Five patients developed symptoms from July to August in summer, belonging to high-temperature operation. They improved by timely treatment. The symptoms, signs and laboratory tests of the five patients were different, but they were diagnosed as occupational heat illness. Conclusion: Employers should pay attention to the high temperature protection and cooling work, and strengthen the labor protection. If patients with heat cramp and heat exhaustion were timely treated, they could basically recover. Occupational disease diagnosticians should seriously study the new diagnostic criteria of occupational disease and constantly improve their diagnostic ability.
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First Measurement of the Decay Asymmetry in the Pure W-Boson-Exchange Decay Λ_{c}^{+}→Ξ^{0}K^{+}. PHYSICAL REVIEW LETTERS 2024; 132:031801. [PMID: 38307076 DOI: 10.1103/physrevlett.132.031801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Accepted: 11/30/2023] [Indexed: 02/04/2024]
Abstract
Based on 4.4 fb^{-1} of e^{+}e^{-} annihilation data collected at the center-of-mass energies between 4.60 and 4.70 GeV with the BESIII detector at the BEPCII collider, the pure W-boson-exchange decay Λ_{c}^{+}→Ξ^{0}K^{+} is studied with a full angular analysis. The corresponding decay asymmetry is measured for the first time to be α_{Ξ^{0}K^{+}}=0.01±0.16(stat)±0.03(syst). This result reflects the noninterference effect between the S- and P-wave amplitudes. The phase shift between S- and P-wave amplitudes has two solutions, which are δ_{p}-δ_{s}=-1.55±0.25(stat)±0.05(syst) rad or 1.59±0.25(stat)±0.05(syst) rad.
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Test of CP Symmetry in Hyperon to Neutron Decays. PHYSICAL REVIEW LETTERS 2023; 131:191802. [PMID: 38000397 DOI: 10.1103/physrevlett.131.191802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Accepted: 10/03/2023] [Indexed: 11/26/2023]
Abstract
The quantum entangled J/ψ→Σ^{+}Σ[over ¯]^{-} pairs from (1.0087±0.0044)×10^{10} J/ψ events taken by the BESIII detector are used to study the nonleptonic two-body weak decays Σ^{+}→nπ^{+} and Σ[over ¯]^{-}→n[over ¯]π^{-}. The CP-odd weak decay parameters of the decays Σ^{+}→nπ^{+} (α_{+}) and Σ[over ¯]^{-}→n[over ¯]π^{-} (α[over ¯]_{-}) are determined to be 0.0481±0.0031_{stat}±0.0019_{syst} and -0.0565±0.0047_{stat}±0.0022_{syst}, respectively. The decay parameter α[over ¯]_{-} is measured for the first time, and the accuracy of α_{+} is improved by a factor of 4 compared to the previous results. The simultaneously determined decay parameters allow the first precision CP symmetry test for any hyperon decay with a neutron in the final state with the measurement of A_{CP}=(α_{+}+α[over ¯]_{-})/(α_{+}-α[over ¯]_{-})=-0.080±0.052_{stat}±0.028_{syst}. Assuming CP conservation, the average decay parameter is determined as ⟨α_{+}⟩=(α_{+}-α[over ¯]_{-})/2=-0.0506±0.0026_{stat}±0.0019_{syst}, while the ratios α_{+}/α_{0} and α[over ¯]_{-}/α[over ¯]_{0} are -0.0490±0.0032_{stat}±0.0021_{syst} and -0.0571±0.0053_{stat}±0.0032_{syst}, where α_{0} and α[over ¯]_{0} are the decay parameters of the decays Σ^{+}→pπ^{0} and Σ[over ¯]^{-}→p[over ¯]π^{0}, respectively.
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Measurement of Energy-Dependent Pair-Production Cross Section and Electromagnetic Form Factors of a Charmed Baryon. PHYSICAL REVIEW LETTERS 2023; 131:191901. [PMID: 38000396 DOI: 10.1103/physrevlett.131.191901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Revised: 08/29/2023] [Accepted: 09/15/2023] [Indexed: 11/26/2023]
Abstract
We study the process e^{+}e^{-}→Λ_{c}^{+}Λ[over ¯]_{c}^{-} at twelve center-of-mass energies from 4.6119 to 4.9509 GeV using data samples collected by the BESIII detector at the BEPCII collider. The Born cross sections and effective form factors (|G_{eff}|) are determined with unprecedented precision after combining the single and double-tag methods based on the decay process Λ_{c}^{+}→pK^{-}π^{+}. Flat cross sections around 4.63 GeV are obtained and no indication of the resonant structure Y(4630), as reported by Belle, is found. In addition, no oscillatory behavior is discerned in the |G_{eff}| energy dependence of Λ_{c}^{+}, in contrast to what is seen for the proton and neutron cases. Analyzing the cross section together with the polar-angle distribution of the Λ_{c}^{+} baryon at each energy point, the moduli of electric and magnetic form factors (|G_{E}| and |G_{M}|) are extracted and separated. For the first time, the energy dependence of the form factor ratio |G_{E}/G_{M}| is observed, which can be well described by an oscillatory function.
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Determination of Spin-Parity Quantum Numbers for the Narrow Structure near the pΛ[over ¯] Threshold in e^{+}e^{-}→pK^{-}Λ[over ¯]+c.c. PHYSICAL REVIEW LETTERS 2023; 131:151901. [PMID: 37897776 DOI: 10.1103/physrevlett.131.151901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 08/22/2023] [Accepted: 09/15/2023] [Indexed: 10/30/2023]
Abstract
A narrow structure in the pΛ[over ¯] system near the mass threshold, named as X(2085), is observed in the process e^{+}e^{-}→pK^{-}Λ[over ¯] with a statistical significance greater than 20σ. Its spin and parity are determined for the first time to be J^{P}=1^{+} in an amplitude analysis, with a statistical significance greater than 5σ over other quantum numbers (0^{-},1^{-} and 2^{+}). The pole positions of X(2085) are measured to be M_{pole}=(2084_{-2}^{+4}±9) MeV and Γ_{pole}=(58_{-3}^{+4}±25) MeV, where the first uncertainties are statistical and the second ones are systematic. The analysis is based on the study of the process e^{+}e^{-}→pK^{-}Λ[over ¯] and uses the data samples collected with the BESIII detector at the center-of-mass energies sqrt[s]=4.008, 4.178, 4.226, 4.258, 4.416, and 4.682 GeV with a total integrated luminosity of 8.35 fb^{-1}.
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Precise Measurement of the e^{+}e^{-}→D_{s}^{*+}D_{s}^{*-} Cross Sections at Center-of-Mass Energies from Threshold to 4.95 GeV. PHYSICAL REVIEW LETTERS 2023; 131:151903. [PMID: 37897771 DOI: 10.1103/physrevlett.131.151903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 08/16/2023] [Accepted: 08/29/2023] [Indexed: 10/30/2023]
Abstract
The process e^{+}e^{-}→D_{s}^{*+}D_{s}^{*-} is studied with a semi-inclusive method using data samples at center-of-mass energies from threshold to 4.95 GeV collected with the BESIII detector operating at the Beijing Electron Positron Collider. The Born cross sections of the process are measured for the first time with high precision in this energy region. Two resonance structures are observed in the energy-dependent cross sections around 4.2 and 4.4 GeV. By fitting the cross sections with a coherent sum of three Breit-Wigner amplitudes and one phase-space amplitude, the two significant structures are assigned masses of (4186.8±8.7±30) and (4414.6±3.4±6.1) MeV/c^{2}, widths of (55±15±53) and (122.5±7.5±8.1) MeV, where the first errors are statistical and the second ones are systematic. The inclusion of a third Breit-Wigner amplitude is necessary to describe a structure around 4.79 GeV.
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First Experimental Study of the Purely Leptonic Decay D_{s}^{*+}→e^{+}ν_{e}. PHYSICAL REVIEW LETTERS 2023; 131:141802. [PMID: 37862669 DOI: 10.1103/physrevlett.131.141802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 07/25/2023] [Accepted: 09/05/2023] [Indexed: 10/22/2023]
Abstract
Using 7.33 fb^{-1} of e^{+}e^{-} collision data taken with the BESIII detector at the BEPCII collider, we report the first experimental study of the purely leptonic decay D_{s}^{*+}→e^{+}ν_{e}. Our data contain a signal of this decay with a statistical significance of 2.9σ. The branching fraction of D_{s}^{*+}→e^{+}ν_{e} is measured to be (2.1_{-0.9_{stat}}^{+1.2}±0.2_{syst})×10^{-5}, corresponding to an upper limit of 4.0×10^{-5} at the 90% confidence level. Taking the total width of the D_{s}^{*+} [(0.070±0.028) keV] predicted with the radiative D_{s}^{*+} decay from the lattice QCD calculation as input, the decay constant of the D_{s}^{*+} is determined to be f_{D_{s}^{*+}}=(214_{-46_{stat}}^{+61}±44_{syst}) MeV, corresponding to an upper limit of 354 MeV at the 90% confidence level.
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All-in-One Online Radiotherapy for Nasopharyngeal Carcinoma: Preliminary Results of Treatment Time, Contouring Accuracy, Treatment Plan Quality and Patient Compliance. Int J Radiat Oncol Biol Phys 2023; 117:e636-e637. [PMID: 37785898 DOI: 10.1016/j.ijrobp.2023.06.2040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) To explore the feasibility of Fan-beam CT (FBCT)-based all in one (AIO) online workflow for nasopharyngeal carcinoma (NPC) in radical radiotherapy setting, and to preliminarily describe the timing of different steps in the process, contouring accuracy of regions of interest (ROIs), target coverage, organs at risk (OARs) dose and patient compliance. MATERIALS/METHODS From March 16, 2022 to January 04, 2023, 25 NPC patients (22/25 diagnosed as phase III/IV disease according to 8th edition of the AJCC/UICC staging system) consecutively treated with AIO radiotherapy were prospectively enrolled. All patients received mask fixation and MRI simulation scan in advance. Primary gross tumor volume (GTVp) of nasopharynx was automatically delineated by AI and edited manually on MRI images. AIO online workflow started with an integrated KV-level CT in a CT-integrated linear accelerator. After that GTVp was registrated to CT images and other ROIs was contoured automatically and then modified manually as needed. Subsequently automatic treatment plan was calculated and optimized until the dose of target and OARs was evaluated satisfactory by physicians and physicists. Finally, treatment was delivered using volumetric modulated arc treatment (VMAT), with prescribed dose of 6996 cGy/ 33 fractions to the GTVp. RESULTS Twenty-four patients (24/25, 96%) completed the AIO radiotherapy workflow successfully, with average treatment time of 28.3 min (range: 19.9-42.4 min). the AI-assisted ROIs automatically contouring took 1.55 min in average (range: 1.32-1.77 min), with an average DICE of 97.7% compared with modified contouring, and the average DICE was 95.7% for clinical tumor volume 1 (CTV1), 88.6% for CTV2, 73.6% for GTVn (cervical lymph node), 99.3% for 30 OARs. The automatic treatment plan averagely needed 3.5 min, and the pass rate of radiotherapy planning was 91.7% (22/24). The target coverage for PTVs for GTVp, CTV1, and CTV2 was 99.3%, 99.8%, 98.0% respectively. As for the dose of OARs, the average Dmax of brainstem was 5,583cGy; the Dmax of spinal cord was 3,467cGy; the Dmean of parotid was 3,285 cGy. The average monitor units of all patients was 643 MU and the delivery took 2.93 min. Patient compliance with respect to AIO workflow and total treatment time was excellent. CONCLUSION The AIO online radiotherapy was promising for NPC patients, with clinically acceptable AI assisted ROIs contouring and treatment planning, as well as favorable patient compliance to the AIO online workflow.
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Automated Contouring of Cervical Lymph Nodes and Clinical Target Volumes for Nasopharyngeal Carcinoma Based on Deep Learning and Experience Constraints. Int J Radiat Oncol Biol Phys 2023; 117:e598. [PMID: 37785805 DOI: 10.1016/j.ijrobp.2023.06.1957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Application of artificial intelligence (AI) for automated contouring of tumor volumes and organs at risk (OARs) for radiotherapy of nasopharyngeal carcinoma (NPC) leads to improved contouring accuracy and efficiency. However, few studies have involved the automated contouring of gross tumor volume of cervical lymph nodes (GTVn) and clinical target volumes (CTVs). In this work, we proposed an AI automated contouring tool for GTVn and CTVs for radiotherapy of NPC on the plain scans of planning compute tomography (CT). MATERIALS/METHODS In this retrospective study, plain scan datasets of planning CT covering the nasopharynx and neck from 139 patients with NPC between March 2022 and December 2022 were collected and divided into training, validation, and testing cohorts of 95, 24, and 20 patients, respectively. Ground truth contours of primary gross tumor volume (GTVp), GTVn (divided into GTVn_L in left neck and GTVn_R in right neck), CTVs (including high risk CTV1 contains GTVp and low risk CTV2 contains GTVp and cervical nodal levels) and OARs were delineated and were defined by consensus of two experts. We first proposed a three-dimensional (3D) U-net using GTVp and OARs as experience constrains to guide the automated delineation of GTVn and CTVs. The average Dice similarity coefficient (DSC) and average surface distance (ASD) were used to quantify the performance of the AI tool. Next, five prospective patients were enrolled for clinical evaluation of our AI tool. DSC between automated contours and radiation oncologist-revised contours and time consuming of the revision were record. RESULTS Clinical characteristics of 139 retrospective and 5 prospective patients are list in Table 1. In the independent testing set of 20 patients, our AI tool showed high performance in GTVn and CTVs contouring when compared with the ground truth contours. The mean DSC were 0.73 ± 0.07, 0.74 ± 0.05, 0.93 ± 0.03, and 0.88 ± 0.03, and the mean ASD were 1.01 ± 0.43 mm, 1.14 ± 0.61 mm, 0.51 ± 0.13 mm, 1.17 ± 0.43 mm for GTVn_L, GTVn_R, CTV1 and CTV2, respectively. In the five prospective patients, mean DSC were 0.74 ± 0.07, 0.74 ± 0.10, 0.95 ± 0.01 and 0.89 ± 0.04, respectively. The median time consuming for GTVn and CTVs revision was 2minutes and 10 seconds (range, 1 minutes to 3 minutes). CONCLUSION The proposed AI tool integrating clinical experience as constrains showed high accuracy for contouring GTVn and CTVs of NPC. With the assistance of AI contours, contouring efficiency could be probably increased, which is promising in online adaptive radiotherapy of NPC.
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First Implementation of Full-Workflow Automation for Online Adaptive Radiotherapy of Nasopharyngeal Carcinoma. Int J Radiat Oncol Biol Phys 2023; 117:e687. [PMID: 37786019 DOI: 10.1016/j.ijrobp.2023.06.2156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) The aim of this work is to established the technical characteristics and implementation procedures of an artificial intelligence (AI)-powered radiotherapy workflow that enables full-process automation for online adaptive radiotherapy (ART); and evaluate its feasibility and performance implemented for ART of nasopharyngeal carcinoma (NPC). MATERIALS/METHODS This single center, prospective study has been approved by the ethical committee of the institution. The online ART workflow was developed based on a CT-integrated linear accelerator. During the course of radiotherapy, the patient underwent daily pre-treatment fan-beam CT (FBCT) scan. Then the FBCT was automatically registered to the original planning CT and used to assess the need for the patient to implement ART according to radiation oncologist's discretionary. The online ART workflow incorporates critical radiotherapy procedures from re-simulation, auto-segmentation by integrating image fusion and deep learning method, auto-replanning, beam delivery, and in vivo quality assurance (QA) into one scheme, while the patient is on the treatment couch during the whole process. RESULTS From 2th April 2022 to 5th January 2023, 20 patients with newly-diagnosed, non-metastatic NPC were enrolled in this study. Only one-time online ART was performed for each patient, because that the appropriate timing for triggering online ART was explored in parallel with this study. According to radiation oncologists' discretionary, the median fraction for performing online ART was at 21 fractions (interquartile range, 19-24 fractions). All patients were well tolerated and successfully completed the treatment. For tumor targets contouring, minor revisions were required for automated contours of the primary gross tumor volume (GTVp) and clinical target volumes (CTVs, including CTV1 and CTV2), with the mean DSC between before and after revision of 0.91±0.042, 0.94 ± 0.042 and 0.91 ± 0.061, respectively; and much more revisions for the automated contours of cervical lymph nodes GTV (GTVn), with the mean DSC of 0.74 ± 0.28. The automated contours of normal tissues were clinically acceptable with little modifications. Median time consuming for auto-segmentation and revision was 9.5 minutes (min). For treatment planning, 18 automated plans (90%) were passed at their first auto-optimization and two plans (10%) were passed after further optimization of the dose coverage of CTVs by physicist; and the median time consuming for auto-planning was 6.2 min. Time consuming for other procedures were as follows: re-simulation, 2.3 min; plan evaluation, 3.3 min; beam delivery, 4.6 min; and the duration of the entire process was 25.9 min, range from 19.4 min to 32.5 min. CONCLUSION We successfully established an AI-powered online ART workflow for adaptive radiotherapy of NPC, and confirmed that current auto-segmentation and auto-replanning methods are powered enough to support the clinical application of its online ART.
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Dosimetric Benefits of Online Adaptive Radiotherapy in Nasopharyngeal Carcinoma. Int J Radiat Oncol Biol Phys 2023; 117:e635-e636. [PMID: 37785896 DOI: 10.1016/j.ijrobp.2023.06.2038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Online adaptive radiotherapy (ART) has the advantage of compensating for potential underdosing to targets and overdosing to organs-at-risk (OARs) caused by variations in patient anatomy and tumor geometry. Artificial intelligence (AI)-assisted rapid generation of new plans makes online ART possible. We aimed to evaluate the dosimetric benefits of online ART on tumor coverage and OARs sparing in nasopharyngeal carcinoma (NPC). MATERIALS/METHODS Twenty patients diagnosed with NPC (19 with stage III and 1 with stage II according to the 8th edition of the AJCC/UICC staging system) who underwent definitive radiotherapy or concurrent chemoradiotherapy and received online ART on CT-Linac between April 2022 and December 2022 were included in this study, consisting of 14 males and 6 females with a median age of 48 years (range: 29-68 years). The prescription dose was 6996 cGy/33 fractions for primary gross tumor volume (GTVp), 6600-6996 cGy/33 fractions for gross tumor volume of nodes (GTVn), 6006 cGy/33 fractions for high-risk clinical tumor volume (CTV1), 5412 cGy/33 fractions for low-risk clinical tumor volume (CTV2). The majority of the patients (15/20) received online ART during the fourth to fifth week of their radiotherapy treatment The auto-segmented contours and auto-plan generated by AI were manually reviewed and edited by radiotherapists and physicists. The paired samples t-test was used to compare the dose and volumes metrics of targets and OARs between scheduled plan and online ART plan. RESULTS The results of this study showed that compared to the scheduled plan, the online ART plan resulted in significant reductions in the volumes of all targets and 8/12 OARs (temporal lobes, optic nerves, lenses, eyes, parotids, submandibulars, mandibles, and thyroid) (P<0.05). The online ART plan also improved target coverage, with D98% for GTVp in the scheduled plan compared to the online ART plan being 7063.4 ± 76.1 cGy and 7096.1 ± 53.9 cGy (P = 0.1), CTV1 being 6266.7 ± 114.9 cGy and 6208.7 ± 54.7 cGy (P<0.05), and CTV2 being 4142.5 ± 1700.9 cGy and 5416.4 ± 23.8 cGy (P<0.01), respectively. The dose to all 12 OARs was reduced with the use of online ART, with 5/12 OARs showing statistical significance. The D0.03cm3 for the spinal cord in the scheduled plan and online ART plan were 3630.9 ± 197.6 and 3454.1 ± 132.0 cGy; for the temporal lobes were 7075.2 ± 303.0 and 6994.2 ± 345.1 cGy; and 4396.0 ± 2575.0 and for the pituitary were 4214.5 ± 2499.2 cGy. Meanwhile the Dmean for the eyes in the scheduled plan and online ART plan was 769.0 ± 232.0 and 714.8 ± 200.1 cGy; and for the mandibles were 3187.7 ± 211.5 and 3066.0 ± 152.1 cGy. CONCLUSION Online ART was effective in protecting most of the OARs in NPC patients, while simultaneously indicating a trend towards enhancing target coverage. This study demonstrated the promising potential of online ART for patients with NPC. This approach will be tested in an upcoming phase III trial.
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A Feasible Study for Auto Planning and Auto Re-Planning for Nasopharyngeal Carcinoma (NPC) Adaptive Radiation Therapy (ART). Int J Radiat Oncol Biol Phys 2023; 117:e739. [PMID: 37786146 DOI: 10.1016/j.ijrobp.2023.06.2271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) To explore the necessity of Image Guided Radiation Therapy (IGRT) for Nasopharyngeal Carcinoma (NPC) adaptive radiation therapy (ART), and evaluate the consistency and robustness of auto re-planning during ART. MATERIALS/METHODS Eleven NPC patients were enrolled in this study at one institution. We used a CT-integrated linear accelerator, which integrates a 16-slice helical CT to acquire diagnostic-grade fan-beam CT (FBCT) for IGRT. Electron density accuracy from FBCT provides a solid foundation for accurate radiation dose calculation. PGTVp, PTV1 and PTV2 prescription dose are 69.96 Gy, 60.06 Gy and 54.12 Gy with 33 fractions. All ROIs, including Targets and OARs, were auto delineated via a treatment planning system (TPS), and modified by a senior physician with more than 15-year experience to confirm that they follow the clinical requirement. An initial plan (Plan A) was automatically generated based on the first CT-Sim images on the TPS. Another adjusted re-plan (Plan B) was also automatically generated based on the second CT-Sim images after 20 fractions of treatment for ART implementation. During the whole course of the 33 fractions delivery, there are 20 fractions Plan A (with 4 weekly IGRTi, i = 1∼4) and 13 fractions Plan B (with 3 weekly IGRTj, j = 5∼7). After carefully rigid registration between the CT-Sim images and their following weekly FBCT images, we copied Plan A and Plan B to IGRTi and IGRTj, respectively. Plan_IGRT would be re-calculated for dose evaluation. In addition, the Plan A was copied to the second CT-Sim (Plan A_2nd CT-Sim) after first CT-Sim and second CT-Sim rigid images registration. RESULTS There is a significant target volume change of -5%±4%, -3%±3%, and -5%±3% from Plan A to Plan B, for PGTVp, PTV1 and PTV2 (p<0.05), respectively. All the Plan A and Plan B could be generated within 210.2s±1.4s, which is more time-saving than manual planning greatly, and there is no statistical difference between Plan A and Plan B of the plan quality index (p>0.05). The plans for IGRT7 are inferior to the plans for IGRT5 with higher V110% for PGTVp (4.40%±8.60% for Plan A, 2.37%±8.91% for Plan B). PlanA_2nd CT-Sim for each patient is inferior to Plan B, with higher V110% for PGTVp (19.12%±18.91%), lower V100% for PTV2 (-2.84%±2.89%) and higher Dmax for Brainstem (315.88 cGy ± 190.39 cGy) statistically. Furthermore, all the Plan B_IGRTj are superior to Plan A_IGRTj, with the dose index difference of -17.50% ± 23.15%/-15.47% ± 14.85%, 2.45% ± 3.23%/2.31% ± 3.09% and -194.03 cGy ± 221.91 cGy/-170.07 cGy ± 168.41 cGy for V110% of PGTVp, V100% for PTV2 and Dmax of Brainstem for j = 5/7 (p<0.05), respectively. CONCLUSION The world's first integrated CT-Linac platform, equipped with FBCT, can provide a diagnostic-quality FBCT for achieve offline ART. It is necessary for NPC patients to have the IGRT, ART and re-planning after 20 fractions treatment, for the target volumes change sharply. Auto planning and auto re-planning for NPC ART are able to maintain the plan consistency and robustness while shorten the planning time.
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[Mechanisms of trained immunity and impacts on atherosclerosis]. ZHONGHUA XIN XUE GUAN BING ZA ZHI 2023; 51:879-886. [PMID: 37583340 DOI: 10.3760/cma.j.cn112148-20230701-00386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 08/17/2023]
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[Change trends and related risk factors of disease burden on mesothelioma in Jiangsu Province from 1990 to 2019]. ZHONGHUA LAO DONG WEI SHENG ZHI YE BING ZA ZHI = ZHONGHUA LAODONG WEISHENG ZHIYEBING ZAZHI = CHINESE JOURNAL OF INDUSTRIAL HYGIENE AND OCCUPATIONAL DISEASES 2023; 41:594-600. [PMID: 37667155 DOI: 10.3760/cma.j.cn121094-20220815-00400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 09/06/2023]
Abstract
Objective: To analyze the change trends and risk factors of mesothelioma disease burden in Jiangsu Province from 1990 to 2019. Methods: In January 2022, using the 2019 Global Burden of Disease Study Data, the Joinpoint regression model was used to analyze the change trends of incidence, mortality, disable-adjusted life years (DALY) and premature mortality of mesothelioma residents in Jiangsu Province from 1990 to 2019, and the attribution level of mesothelioma risk factors was estimated by population attributing fraction. Results: The standardized incidence rates of mesothelioma in Jiangsu Province from 1990 to 2019 ranged from 0.07/10(5) to 0.09/10(5), with an average annual percentage change (AAPC) of -1.1% (t=-13.56, P<0.001). AAPCs in males and females were -0.3% (t=-2.18, P=0.029) and -1.6% (t=-11.39, P<0.001), respectively. The standardized mortality rates of mesothelioma ranged from 0.07/10(5) to 0.09/10(5), the AAPC was -1.1% (t=-12.23, P<0.001), AAPC was -1.6% (t=-14.09, P<0.001) for females, and there was no significant change in males (t=-1.83, P=0.068). The premature mortality was 0.004%-0.006%, the AAPC was -1.0% (t=-4.40, P<0.001), AAPC was -1.7% (t=-13.72, P<0.001) for females, and there was no significant change in males (t=-0.68, P=0.495). The standardized DALY rates ranged from 1.86/10(5) to 2.32/10(5), the AAPC was -0.9% (t=-11.08, P<0.001), AAPC was -1.6% (t=-11.05, P<0.001) for females, and there was no significant change in males (t=-0.95, P=0.343). Both the standardized years of life lost (YLL) rate and the standardized years lived with disability (YLD) rate showed a decreasing trend, and the AAPCs were -0.9% (t=-7.66, P<0.001) and -1.0% (t=-12.88, P<0.001), respectively. The proportion of YLL in DALY was more than 98.5%. Among the risk factors for mesothelioma burden attribution, the AAPC attributed to occupational asbestos exposure of DALY was 1.4% (t=3.43, P=0.001). The AAPC of DALY rate of standardized attribution was -1.7% (t=-12.11, P<0.001) . Conclusion: The overall burden of mesothelioma in Jiangsu Province is decreasing, occupational asbestos exposure is still the main risk factor of mesothelioma in Jiangsu Province, and early diagnosis and treatment should be strengthened.
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[Regulatory effects of the Nocardia rubra cell wall skeleton on the biological function of human neutrophils]. ZHONGHUA SHAO SHANG YU CHUANG MIAN XIU FU ZA ZHI 2023; 39:625-632. [PMID: 37805691 DOI: 10.3760/cma.j.cn501225-20230223-00056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 10/09/2023]
Abstract
Objective: To investigate the regulatory effects and mechanism of Nocardia rubra cell wall skeleton (Nr-CWS) on the biological function of human neutrophils. Methods: The experimental research method was used. Fifteen healthy adult volunteers (7 males and 8 females, aged 24 to 45 years) were recruited from Suzhou Physical Examination Center for physical examination from May to October 2022, the peripheral venous blood was collected, and neutrophils were extracted by immunomagnetic bead sorting. The cells were divided into normal control group without any treatment, Nr-CWS alone group treated with Nr-CWS of final mass concentration 60 ng/mL alone, endotoxin/lipopolysaccharide (LPS) alone group stimulated with LPS of final mass concentration 1 μg/mL alone, and LPS+Nr-CWS group stimulated with LPS first and then treated with Nr-CWS as before. After 1 h of culture, the chemotaxis distance, chemotactic cell percentage, chemotactic index, maximum chemotactic speed, and chemotactic function score of neutrophils were detected using the modified agarose chemotactic model; the proportion and fluorescence intensity of phagocytosis cells, the level of reactive oxygen species (ROS), the protein expression levels of granular protein CD35, CD66b, and CD63, and the concentrations of inflammatory cytokines of interleukin 2 (IL-2), IL-4, IL-6, IL-10, IL-17A, tumor necrosis factor alpha (TNF-α), and interferon-γ in cell culture supernatant were detected by flow cytometry. The number of samples in each group in the above experiments was 15. Data were statistically analyzed with analysis of variance for factorial design and independent sample t test. Results: After 1 h of culture, the chemotactic function score of cells in normal control group, Nr-CWS alone group, LPS alone group, and LPS+Nr-CWS group were 15.0, 14.5±0.5, 1.5±0.5, 12.0±1.5, respectively. Compared with those in normal control group, the chemotaxis distance, chemotactic cell percentage, chemotactic index, maximum chemotactic speed, and chemotactic function score of cells were significantly decreased in LPS alone group and LPS+Nr-CWS group (with t values of 18.36, 18.88, 54.28, 18.36, 46.77, 10.58, 14.74, 6.84, 10.58, and 4.24, respectively, P<0.05); compared with those in LPS alone group, the five chemotactic function indexes as above in LPS+Nr-CWS group were significantly increased (with t values of 11.47, 14.65, 11.62, 11.47, and 13.75, respectively, P<0.05). After 1 h of culture, compared with those in normal control group, the proportion and fluorescence intensity of phagocytosis cells were significantly increased in Nr-CWS alone group (with t values of 6.86 and 6.73, respectively, P<0.05), and the above two indexes were significantly decreased in LPS alone group (with t values of 7.35 and 22.72, respectively, P<0.05) and LPS+Nr-CWS group (with t values of 21.37 and 13.10, respectively, P<0.05). After 1 h of culture, compared with that in normal control group, the level of ROS of cells in LPS alone group was significantly increased (t=6.64, P<0.05); compared with that in LPS alone group, the level of ROS of cells in LPS+Nr-CWS group was significantly decreased (t=5.46, P<0.05). After 1 h of culture, compared with those in normal control group, the protein expressions of CD35, CD66b, and CD63 of cells were significantly increased in LPS alone group and LPS+Nr-CWS group (with t values of 16.75, 17.45, 10.82, 5.70, 19.35, and 15.37, respectively, P<0.05); compared with those in LPS alone group, the protein expressions of CD35, CD66b, and CD63 of cells were significantly decreased in LPS+Nr-CWS group (with t values of 4.92, 5.72, and 3.18, respectively, P<0.05). After 1 h of culture, compared with those in normal control group, the concentrations of IL-2, IL-4, IL-6, IL-10, IL-17A, TNF-α, and interferon-γ in cell culture supernatant were significantly increased in LPS alone group (with t values of 22.10, 9.50, 7.21, 10.22, 24.88, 8.43, and 47.48, respectively, P<0.05), and the concentrations of IL-6, IL-10, IL-17A, TNF-α, and interferon-γ in cell culture supernatant were significantly increased in LPS+Nr-CWS group (with t values of 4.68, 5.12, 8.02, 5.58, and 7.13, respectively, P<0.05); compared with those in LPS alone group, the concentrations of IL-2, IL-4, IL-6, IL-10, IL-17A, TNF-α, and interferon-γ in cell culture supernatant were significantly decreased in LPS+Nr-CWS group (with t values of 5.39, 2.83, 5.79, 2.90, 5.87, 4.88, and 39.64, respectively, P<0.05). Conclusions: Nr-CWS can enhance the phagocytosis ability of neutrophils in normal condition and improve the chemotactic function, ROS level, degranulation protein level, and inflammatory factor level of human neutrophils in infectious condition. Nr-CWS can enhance the anti-infection ability of human neutrophils by regulating its biological behavior in innate immunity.
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First Study of Reaction Ξ^{0}n→Ξ^{-}p Using Ξ^{0}-Nucleus Scattering at an Electron-Positron Collider. PHYSICAL REVIEW LETTERS 2023; 130:251902. [PMID: 37418739 DOI: 10.1103/physrevlett.130.251902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 05/20/2023] [Accepted: 05/25/2023] [Indexed: 07/09/2023]
Abstract
Using (1.0087±0.0044)×10^{10} J/ψ events collected with the BESIII detector at the BEPCII storage ring, the process Ξ^{0}n→Ξ^{-}p is studied, where the Ξ^{0} baryon is produced in the process J/ψ→Ξ^{0}Ξ[over ¯]^{0} and the neutron is a component of the ^{9}Be, ^{12}C, and ^{197}Au nuclei in the beam pipe. A clear signal is observed with a statistical significance of 7.1σ. The cross section of the reaction Ξ^{0}+^{9}Be→Ξ^{-}+p+^{8}Be is determined to be σ(Ξ^{0}+^{9}Be→Ξ^{-}+p+^{8}Be)=(22.1±5.3_{stat}±4.5_{sys}) mb at the Ξ^{0} momentum of 0.818 GeV/c, where the first uncertainty is statistical and the second is systematic. No significant H-dibaryon signal is observed in the Ξ^{-}p final state. This is the first study of hyperon-nucleon interactions in electron-positron collisions and opens up a new direction for such research.
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[Effects of small GTP-binding protein GDP dissociation stimulator on adipocyte hypertrophy and glucose metabolism disorder in mice]. ZHONGHUA NEI KE ZA ZHI 2023; 62:833-840. [PMID: 37293734 DOI: 10.3760/cma.j.cn112138-20230209-00072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Objective: To explore the effect and mechanism of small GTP-binding protein GDP dissociation stimulator (SmgGDS) on the development of obesity. Methods: (1) 8-week-old C57BL/6J mice were randomly assigned to normal diet and high fat diet group, with 6 mice in each group. They were fed regular feed and a high fat diet containing 60% fat for 4 months, respectively. The expression of SmgGDS in epididymal adipose tissue (eWAT), liver, and skeletal muscle were measured using Western-blot. (2) 6-week-old wild-type (WT) and SmgGDS knockdown (KD) mice were divided into four groups, each receiving high fat diet for 4 months (7 in each group) and 7 months (9 in each group). Glucose tolerance test (GTT) and insulin tolerance test (ITT) were conducted; The weight, adipose tissue, and liver weight of mice were recorded; HE staining examined adipose tissue structural changes; Western-blot determined extracellular signal-regulated kinase (ERK) 1/2 phosphorylation levels in eWAT; Real time fluorescence quantitative polymerase chain reaction (RT-qPCR) was used to detect mRNA levels of CCAAT/enhancer binding protein α (C/EBPα), C/EBPβ and peroxisome proliferator activated receptor γ (PPARγ) in eWAT. (3) Mouse embryonic fibroblasts (MEFs) extracted from WT and KD mice were induced for differentiation. Oil red O staining and Western-blot were used to detect lipid droplet and expression of SmgGDS and phospho-ERK; C/EBPα, C/EBPβ and PPARγ mRNA levels were measured using RT-qPCR. (4) 10-week-old C57BL/6J mice were randomly assigned into two groups, with 7 mice in each group. Mice were infected with SmgGDS overexpressing adeno-associated virus (AAV-SmgGDS) or empty vector intraperitoneally, then fed with high fat diet. After 4 weeks, performed GTT and ITT; Recorded the weight and adipose tissue weight of mice; HE staining was used to analyze structural changes of eWAT; Western-blot was used to detect the phosphorylation level of ERK in eWAT. Results: (1) The expression of SmgGDS was significantly upregulated in eWAT of high fat diet fed mice (normal diet group: 0.218±0.037, high fat diet group:0.439±0.072, t=2.74, P=0.034). (2) At 4 months of high fat diet intervention, the glucose tolerance (60 minutes after glucose injection, WT group: 528 mg/dl±21 mg/dl, KD group: 435 mg/dl±17 mg/dl, t=3.47, P=0.030; 90 minutes, WT group: 463 mg/dl±24 mg/dl, KD group: 366 mg/dl±18 mg/dl, t=3.23, P=0.047;120 minutes, WT group: 416 mg/dl±21 mg/dl, KD group: 297 mg/dl±16 mg/dl, t=4.49, P=0.005) and insulin sensitivity (15 minutes after insulin injection, WT group: 77.79%±3.45%, KD group: 54.30%±2.92%, t=3.49, P=0.005; 30 minutes, WT group: 62.27%±5.31%, KD group: 42.25%±1.85%, t=2.978, P=0.024; 90 minutes, WT group: 85.69%±6.63%, KD group: 64.71%±5.41%, t=3.120, P=0.016) of KD mice were significantly improved compared to the WT group, with an increase in eWAT weight ratio (WT: 4.19%±0.18%, KD: 5.12%±0.37%, t=2.28, P=0.042), but a decrease in average adipocyte area (WT group: 5221 μm²±241 μm², KD group: 4410 μm²±196 μm², t=2.61, P=0.026). After 7 months of high fat diet, the eWAT weight ratio of KD mice decreased (WT: 5.02%±0.20%, KD: 3.88%±0.21%, t=3.92, P=0.001) and adipocyte size decreased (WT group: 6 783 μm²±390 μm², KD group: 4785 μm²±303 μm², t=4.05, P=0.002). The phospho-ERK1 in eWAT increased (WT group: 0.174±0.056, KD group: 0.588±0.147, t=2.64, P=0.025), and mRNA level of PPARγ significantly decreased (WT group: 1.018±0.128, KD group: 0.029±0.015, t=7.70, P=0.015). (3) The expression of SmgGDS was significantly increased in differentiated MEF (undifferentiated: 6.789±0.511, differentiated: 10.170±0.523, t=4.63, P=0.010); SmgGDS knock-down inhibited lipid droplet formation in MEF (WT group: 1.00±0.02, KD group: 0.88±0.02, t=5.05, P=0.007) and increased ERK1 (WT group: 0.600±0.179, KD group: 1.325±0.102, t=3.52, P=0.025) and ERK2 (WT group: 2.179±0.687, KD group: 5.200±0.814, t=2.84, P=0.047) activity, which can be reversed by ERK1/2 inhibitor. (4) SmgGDS over expression resulted in weight gain, increased eWAT weight (control group: 3.29%±0.36%, AAV-SmgGDS group: 4.27%±0.26%, t=2.20, P=0.048) and adipocyte size (control group: 3525 μm²±454 μm², AAV-SmgGDS group: 5326 μm²±655 μm², t=2.26, P=0.047), impaired insulin sensitivity(30 minutes after insulin injection, control group: 44.03%±4.29%, AAV-SmgGDS group: 62.70%±2.81%, t=3.06, P=0.019), and decreased ERK1 (control group: 0.829±0.077, AAV-SmgGDS group: 0.326±0.036, t=5.96, P=0.001)and ERK2 (control group: 5.748±0.287, AAV-SmgGDS group: 2.999±0.845, t=3.08, P=0.022) activity in eWAT. Conclusion: SmgGDS knockdown improves obesity related glucose metabolism disorder by inhibiting adipogenesis and adipose tissue hypertrophy, which is associated with ERK activation.
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Measurements of Normalized Differential Cross Sections of Inclusive π^{0} and K_{S}^{0} Production in e^{+}e^{-} Annihilation at Energies from 2.2324 to 3.6710 GeV. PHYSICAL REVIEW LETTERS 2023; 130:231901. [PMID: 37354421 DOI: 10.1103/physrevlett.130.231901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 03/22/2023] [Accepted: 04/03/2023] [Indexed: 06/26/2023]
Abstract
Based on electron positron collision data collected with the BESIII detector operating at the BEPCII storage rings, the differential cross sections of inclusive π^{0} and K_{S}^{0} production as a function of hadron momentum, normalized by the total cross section of the e^{+}e^{-}→hadrons process, are measured at six center-of-mass energies from 2.2324 to 3.6710 GeV. Our results, which cover a relative hadron energy range from 0.1 to 0.9, significantly deviate from several theoretical calculations based on existing fragmentation functions.
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Precision Measurement of the Decay Σ^{+}→pγ in the Process J/ψ→Σ^{+}Σ[over ¯]^{-}. PHYSICAL REVIEW LETTERS 2023; 130:211901. [PMID: 37295102 DOI: 10.1103/physrevlett.130.211901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 03/29/2023] [Accepted: 05/08/2023] [Indexed: 06/12/2023]
Abstract
Using (10 087±44)×10^{6} J/ψ events collected with the BESIII detector, the radiative hyperon decay Σ^{+}→pγ is studied at an electron-positron collider experiment for the first time. The absolute branching fraction is measured to be (0.996±0.021_{stat}±0.018_{syst})×10^{-3}, which is lower than its world average value by 4.2 standard deviations. Its decay asymmetry parameter is determined to be -0.652±0.056_{stat}±0.020_{syst}. The branching fraction and decay asymmetry parameter are the most precise to date, and the accuracies are improved by 78% and 34%, respectively.
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[Clinical analysis of 15 pregnant women complicated with moyamoya disease]. ZHONGHUA FU CHAN KE ZA ZHI 2023; 58:270-276. [PMID: 37072295 DOI: 10.3760/cma.j.cn112141-20221129-00721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Subscribe] [Scholar Register] [Indexed: 04/20/2023]
Abstract
Objective: To explore the effects of pregnancy complicated with moyamoya disease on maternal and fetal outcomes. Methods: The general clinical data and maternal and fetal outcomes of 20 pregnancies of 15 patients with moyamoya disease admitted to the First Affiliated Hospital of Zhengzhou University from January 2012 to October 2022 were retrospectively analyzed. Results: (1) General information: among the 20 pregnancies of 15 clearly diagnosed pregnant women complicated with moyamoya disease, 12 were diagnosed before pregnancy (60%, 12/20), 3 were diagnosed during pregnancy (15%, 3/20), and 5 were diagnosed during puerperal period (25%, 5/20). There were 7 cases of primipara (35%, 7/20) and 13 cases of multipara (65%, 13/20). (2) Pregnancy complications and maternal and infant outcomes: among the 20 pregnancies of 15 pregnant women with moyamoya disease, there were 9 pregnancy complications (45%, 9/20), including 5 gestational hypertension (25%, 5/20), 2 severe pre-eclampsia (10%, 2/20), 1 hyperlipidemia and 1 gestational diabetes mellitus (5%, 1/20). There were 2 case of drug abortion in the first trimester, 3 cases of labor induction in the second trimester, and 15 cases of delivery during the third trimester. All the 15 deliveries were cesarean section, of which 11 (11/15) were cesarean sections with medical indications, and 4 (4/15) were cesarean sections caused by personal factors. General anesthesia was used in 5 cases (5/15), epidural block anesthesia in 7 cases (7/15), and combined spinal and epidural anesthesia in 3 cases (3/15). The median gestational age of 15 neonates was 37.2 weeks (34.0 to 40.8 weeks), with 10 cases (10/15) were full-term infants, and 5 (5/15) were preterm infants (3 of which were associated with hypertensive disorder complicating pregnancy). The birth weight of 15 neonates was (2 853±454) g. Four neonates were admitted to neonatal intensive care unit (NICU), of which 3 cases were admitted to NICU due to premature delivery and 1 case was admitted to NICU due to neonatal jaundice. There was no neonatal asphyxia or death. All neonates were followed up from 4 months to 6 years after birth, and all grew well. (3) Neurological symptoms during pregnancy: 8 cases (40%, 8/20) had neurological symptoms during pregnancy, and 6 cases (30%, 6/20) had hemorrhagic symptoms, of which 3 cases occurred during the puerperal period (3/6). There were 2 cases of ischemic symptoms (10%, 2/20), all of which occurred during the puerperal period (2/2). (4) Analysis of factors related to the occurrence of cerebral hemorrhage: the incidence of cerebral hemorrhage in patients with moyamoya disease diagnosed before pregnancy was significantly lower than that in those without a clear diagnosis, and the incidence of cerebral hemorrhage in women with moyamoya disease was lower than that in primipara (all P<0.01). The incidence of cerebral hemorrhage in moyamoya patients without hypertensive disorder complicating pregrancy was lower than that in patients with hypertensive disorder complicating pregrancy, but the difference was not statistically significant (P>0.05). Conclusions: Pregnancy combined with moyamoya disease has adverse effects on maternal and infant outcomes, and the incidence of pregnancy complications increases. Cerebral hemorrhage occurres in prenatal and puperium, while cerebral ischemia occurres mainly in puperium.
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Measurements of the Electric and Magnetic Form Factors of the Neutron for Timelike Momentum Transfer. PHYSICAL REVIEW LETTERS 2023; 130:151905. [PMID: 37115883 DOI: 10.1103/physrevlett.130.151905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 02/27/2023] [Accepted: 03/23/2023] [Indexed: 06/19/2023]
Abstract
We present the first measurements of the electric and magnetic form factors of the neutron in the timelike (positive q^{2}) region as function of four-momentum transfer. We explored the differential cross sections of the reaction e^{+}e^{-}→n[over ¯]n with data collected with the BESIII detector at the BEPCII accelerator, corresponding to an integrated luminosity of 354.6 pb^{-1} in total at twelve center-of-mass energies between sqrt[s]=2.0-2.95 GeV. A relative uncertainty of 18% and 12% for the electric and magnetic form factors, respectively, is achieved at sqrt[s]=2.3935 GeV. Our results are comparable in accuracy to those from electron scattering in the comparable spacelike region of four-momentum transfer. The electromagnetic form factor ratio R_{em}≡|G_{E}|/|G_{M}| is within the uncertainties close to unity. We compare our result on |G_{E}| and |G_{M}| to recent model predictions, and the measurements in the spacelike region to test the analyticity of electromagnetic form factors.
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Observation of a New X(3872) Production Process e^{+}e^{-}→ωX(3872). PHYSICAL REVIEW LETTERS 2023; 130:151904. [PMID: 37115900 DOI: 10.1103/physrevlett.130.151904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 03/16/2023] [Accepted: 03/20/2023] [Indexed: 06/19/2023]
Abstract
Using 4.7 fb^{-1} of e^{+}e^{-} collision data at center-of-mass energies from 4.661 to 4.951 GeV collected by the BESIII detector at the BEPCII collider, we observe the X(3872) production process e^{+}e^{-}→ωX(3872) for the first time. The significance is 7.8σ, including both the statistical and systematic uncertainties. The e^{+}e^{-}→ωX(3872) Born cross section and the corresponding upper limit at 90% confidence level at each energy point are reported. The line shape of the cross section indicates that the ωX(3872) signals may be from the decays of some nontrivial structures.
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Observation of Three Charmoniumlike States with J^{PC}=1^{--} in e^{+}e^{-}→D^{*0}D^{*-}π^{+}. PHYSICAL REVIEW LETTERS 2023; 130:121901. [PMID: 37027853 DOI: 10.1103/physrevlett.130.121901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 02/16/2023] [Accepted: 02/24/2023] [Indexed: 06/19/2023]
Abstract
The Born cross sections of the process e^{+}e^{-}→D^{*0}D^{*-}π^{+} at center-of-mass energies from 4.189 to 4.951 GeV are measured for the first time. The data samples used correspond to an integrated luminosity of 17.9 fb^{-1} and were collected by the BESIII detector operating at the BEPCII storage ring. Three enhancements around 4.20, 4.47, and 4.67 GeV are visible. The resonances have masses of 4209.6±4.7±5.9 MeV/c^{2}, 4469.1±26.2±3.6 MeV/c^{2}, and 4675.3±29.5±3.5 MeV/c^{2} and widths of 81.6±17.8±9.0 MeV, 246.3±36.7±9.4 MeV, and 218.3±72.9±9.3 MeV, respectively, where the first uncertainties are statistical and the second systematic. The first and third resonances are consistent with the ψ(4230) and ψ(4660) states, respectively, while the second one is compatible with the ψ(4500) observed in the e^{+}e^{-}→K^{+}K^{-}J/ψ process. These three charmoniumlike ψ states are observed in the e^{+}e^{-}→D^{*0}D^{*-}π^{+} process for the first time.
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Evidence for the Cusp Effect in η' Decays into ηπ^{0}π^{0}. PHYSICAL REVIEW LETTERS 2023; 130:081901. [PMID: 36898113 DOI: 10.1103/physrevlett.130.081901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 11/19/2022] [Accepted: 01/20/2023] [Indexed: 06/18/2023]
Abstract
Using a sample of 4.3×10^{5} η^{'}→ηπ^{0}π^{0} events selected from the ten billion J/ψ event dataset collected with the BESIII detector, we study the decay η^{'}→ηπ^{0}π^{0} within the framework of nonrelativistic effective field theory. Evidence for a structure at π^{+}π^{-} mass threshold is observed in the invariant mass spectrum of π^{0}π^{0} with a statistical significance of around 3.5σ, which is consistent with the cusp effect as predicted by the nonrelativistic effective field theory. After introducing the amplitude for describing the cusp effect, the ππ scattering length combination a_{0}-a_{2} is determined to be 0.226±0.060_{stat}±0.013_{syst}, which is in good agreement with theoretical calculation of 0.2644±0.0051.
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Study of the Semileptonic Decay Λ_{c}^{+}→Λe^{+}ν_{e}. PHYSICAL REVIEW LETTERS 2022; 129:231803. [PMID: 36563214 DOI: 10.1103/physrevlett.129.231803] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 11/01/2022] [Indexed: 06/17/2023]
Abstract
The study of the Cabibbo-favored semileptonic decay Λ_{c}^{+}→Λe^{+}ν_{e} is reported using a 4.5 fb^{-1} data sample of e^{+}e^{-} annihilations collected at center-of-mass energies ranging from 4.600 GeV to 4.699 GeV with the BESIII detector at the BEPCII collider. The branching fraction of the decay is measured to be B(Λ_{c}^{+}→Λe^{+}ν_{e})=(3.56±0.11_{stat}±0.07_{syst})%, which is the most precise measurement to date. Furthermore, we perform an investigation of the internal dynamics in Λ_{c}^{+}→Λe^{+}ν_{e}. We provide the first direct comparisons of the differential decay rate and form factors with those predicted from lattice quantum chromodynamics (LQCD) calculations. Combining the measured branching fraction with a q^{2}-integrated rate predicted by LQCD, we determine |V_{cs}|=0.936±0.017_{B}±0.024_{LQCD}±0.007_{τ_{Λ_{c}}}.
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Measurement of the Absolute Branching Fraction and Decay Asymmetry of Λ→nγ. PHYSICAL REVIEW LETTERS 2022; 129:212002. [PMID: 36461970 DOI: 10.1103/physrevlett.129.212002] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 09/27/2022] [Accepted: 10/24/2022] [Indexed: 06/17/2023]
Abstract
The radiative hyperon decay Λ→nγ is studied using (10087±44)×10^{6} J/ψ events collected with the BESIII detector operating at BEPCII. The absolute branching fraction of the decay Λ→nγ is determined to be (0.832±0.038_{stat}±0.054_{syst})×10^{-3}, which is a factor of 2.1 lower and 5.6 standard deviations different than the previous measurement. By analyzing the joint angular distribution of the decay products, the first determination of the decay asymmetry α_{γ} is reported with a value of -0.16±0.10_{stat}±0.05_{syst}.
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[The purchase behavior of prepackaged food and its determinants among primary and middle school students in 6 provinces of China]. ZHONGHUA YU FANG YI XUE ZA ZHI [CHINESE JOURNAL OF PREVENTIVE MEDICINE] 2022; 56:1604-1611. [PMID: 36372751 DOI: 10.3760/cma.j.cn112150-20211126-01090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Objective: To examine the purchase behaviors of prepackaged food and its determinants among primary and middle school students in 6 provinces of China. Methods: A multi-stage sampling strategy was adopted to select 2 499 primary and middle school students and their parents from the eastern region of China(Beijing, Jiangsu Province, Guangdong Province), the northeast region(Heilongjiang Province), the central region(Henan Province) and the western region(Sichuan Province) from July 2020 to March 2021. Socio-demographic characteristics of students and their parents, eating-related behaviors and the purchase behaviors of prepackaged food of students, and parents' attitudes towards students' eating behavior were collected through questionnaire towards students and their parents. The χ² test was conducted to compare the purchase behaviors in different groups of students, and multivariate logistic stepwise regression analysis was used to analyze the determinants among primary and middle school students. Results: The age of 2 499 participants was(12.7±2.5) years. There were 1 272(50.9%) females and 1 279(51.2%) middle school students. About 1 404(56.2%) students bought prepackaged food. The top 6 prepackaged foods bought at least once a week were milk and dairy products(74.6%), baked food(58.7%), beverages(42.8%), puffed food(40.8%), chocolate and candy(39.8%), and nuts and dried fruits(37.5%). The multivariate logistic regression model analysis results showed that compared with primary school students, rural students, non-boarding students, students who did not like snacks and students whose parents paid attention to their children eating snacks, middle school students(OR=3.36, 95%CI:2.73-4.12), urban students(OR=1.33, 95%CI:1.11-1.61), boarding students(OR=2.15, 95%CI:1.66-2.79), students who liked snacks(OR=2.01, 95%CI:1.66-2.43), students whose parents did not pay attention to their children eating snacks(OR=1.27, 95%CI:1.05-1.54) were more likely to buy prepackaged food by themselves. Compared with students whose parents had education level of junior high school and below, students whose parents had education level of undergraduate and above(OR=0.70, 95%CI:0.53-0.92) were less likely to buy prepackaged food by themselves. Compared with students whose family monthly income was less than 5 000 yuan, students whose family monthly income was over 10 000 yuan(OR=0.67, 95%CI:0.52-0.87) were less likely to buy prepackaged food by themselves. Conclusion: Many primary and middle school students buy prepackaged food by themselves in 6 provinces of China. Individual characteristics such as grade, place of residence, boarding status, as well as family environment such as parents' education level, monthly income and concern about children eating snacks are the influencing factors of purchasing prepackaged food.
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Observation of an Isoscalar Resonance with Exotic J^{PC}=1^{-+} Quantum Numbers in J/ψ→γηη^{'}. PHYSICAL REVIEW LETTERS 2022; 129:192002. [PMID: 36399732 DOI: 10.1103/physrevlett.129.192002] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 05/03/2022] [Accepted: 09/27/2022] [Indexed: 06/16/2023]
Abstract
Using a sample of (10.09±0.04)×10^{9} J/ψ events collected with the BESIII detector operating at the BEPCII storage ring, a partial wave analysis of the decay J/ψ→γηη^{'} is performed. The first observation of an isoscalar state with exotic quantum numbers J^{PC}=1^{-+}, denoted as η_{1}(1855), is reported in the process J/ψ→γη_{1}(1855) with η_{1}(1855)→ηη^{'}. Its mass and width are measured to be (1855±9_{-1}^{+6}) MeV/c^{2} and (188±18_{-8}^{+3}) MeV, respectively, where the first uncertainties are statistical and the second are systematic, and its statistical significance is estimated to be larger than 19σ.
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Observation of an a_{0}-like State with Mass of 1.817 GeV in the Study of D_{s}^{+}→K_{S}^{0}K^{+}π^{0} Decays. PHYSICAL REVIEW LETTERS 2022; 129:182001. [PMID: 36374689 DOI: 10.1103/physrevlett.129.182001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Revised: 07/08/2022] [Accepted: 09/13/2022] [Indexed: 06/16/2023]
Abstract
Using e^{+}e^{-} annihilation data corresponding to an integrated luminosity of 6.32 fb^{-1} collected at center-of-mass energies between 4.178 and 4.226 GeV with the BESIII detector, we perform the first amplitude analysis of the decay D_{s}^{+}→K_{S}^{0}K^{+}π^{0} and determine the relative branching fractions and phases for intermediate processes. We observe an a_{0}-like state with mass of 1.817 GeV in its decay to K_{S}^{0}K^{+} for the first time. In addition, we measure the ratio {B[D_{s}^{+}→K[over ¯]^{*}(892)^{0}K^{+}]/B[D_{s}^{+}→K[over ¯]^{0}K^{*}(892)^{+}]} to be 2.35_{-0.23stat}^{+0.42}±0.10_{syst}. Finally, we provide a precision measurement of the absolute branching fraction B(D_{s}^{+}→K_{S}^{0}K^{+}π^{0})=(1.46±0.06_{stat}±0.05_{syst})%.
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Regulatory role of phosphoproteins in the development of bovine small intestine during early life. J Dairy Sci 2022; 105:9240-9252. [PMID: 36175223 DOI: 10.3168/jds.2022-21983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 06/20/2022] [Indexed: 11/19/2022]
Abstract
The small intestine is the primary site of nutrient digestion and absorption, which plays a key role in the survival of neonatal calves. A comprehensive assessment of the phosphoproteomic changes in the small intestine of neonatal calves is unavailable; therefore, we used phosphopeptide enrichment coupled with liquid chromatography-tandem mass spectrometry to investigate the changes in the phosphoproteome profile in the bovine small intestine during the first 36 h of life. Twelve neonatal male calves were assigned to one of the following groups: (1) calves not fed colostrum and slaughtered approximately 2 h postpartum (n = 3), (2) calves fed colostrum at 1 to 2 h and slaughtered 8 h postpartum (n = 3), (3) calves fed 2 colostrum meals (at 1-2 and 10-12 h) and slaughtered 24 h postpartum (n = 3), (4) calves fed 3 colostrum meals (at 1-2, 10-12, and 22-24 h) and slaughtered 36 h postpartum (n = 3). Mid-duodenal, jejunal, and ileal samples of the calves were collected after slaughter. We identified 1,678 phosphoproteins with approximately 3,080 phosphosites, which were mainly Ser (89.9%), Thr (9.8%), and Tyr (0.3%) residues; they belonged to the prodirected (52.9%), basic (20.4%), acidic (16.6%), and Tyr-directed (1.7%) motif categories. The regional differentially expressed phosphoproteins included zonula occludens 2, sorting nexin 12, and protein kinase C, which are mainly associated with developmental processes, intracellular transport, vesicle-mediated transport, and immune system process. They are enriched in the endocytosis, tight junction, insulin signaling, and focal adhesion pathways. The temporal differentially expressed phosphoproteins included occludin, epsin 1, and bridging integrator 1, which were mainly associated with macromolecule metabolic process, cell adhesion, and growth. They were enriched in the spliceosomes, adherens junctions, and tight junctions. The observed changes in the phosphoproteins in the tissues of small intestine suggest the protein phosphorylation plays an important role in nutrient transport and immune response of calves during early life, which needs to be confirmed in a larger study.
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Precise Measurements of Decay Parameters and CP Asymmetry with Entangled Λ-Λ[over ¯] Pairs. PHYSICAL REVIEW LETTERS 2022; 129:131801. [PMID: 36206435 DOI: 10.1103/physrevlett.129.131801] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 09/01/2022] [Indexed: 06/16/2023]
Abstract
Based on 10 billion J/ψ events collected at the BESIII experiment, a search for CP violation in Λ decay is performed in the difference between CP-odd decay parameters α_{-} for Λ→pπ^{-} and α_{+} for Λ[over ¯]→p[over ¯]π^{+} by using the process e^{+}e^{-}→J/ψ→ΛΛ[over ¯]. With a five-dimensional fit to the full angular distributions of the daughter baryon, the most precise values for the decay parameters are determined to be α_{-}=0.7519±0.0036±0.0024 and α_{+}=-0.7559±0.0036±0.0030, respectively. The Λ and Λ[over ¯] averaged value of the decay parameter is extracted to be α_{avg}=0.7542±0.0010±0.0024 with unprecedented accuracy. The CP asymmetry A_{CP}=(α_{-}+α_{+})/(α_{-}-α_{+}) is determined to be -0.0025±0.0046±0.0012, which is one of the most precise measurements in the baryon sector. The reported results for the decay parameter will play an important role in the studies of the polarizations and CP violations for the strange, charmed and beauty baryons.
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First Observation of the Direct Production of the χ_{c1} in e^{+}e^{-} Annihilation. PHYSICAL REVIEW LETTERS 2022; 129:122001. [PMID: 36179210 DOI: 10.1103/physrevlett.129.122001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 06/22/2022] [Accepted: 07/26/2022] [Indexed: 06/16/2023]
Abstract
We study the direct production of the J^{PC}=1^{++} charmonium state χ_{c1}(1P) in electron-positron annihilation by carrying out an energy scan around the mass of the χ_{c1}(1P). The data were collected with the BESIII detector at the BEPCII collider. An interference pattern between the signal process e^{+}e^{-}→χ_{c1}(1P)→γJ/ψ→γμ^{+}μ^{-} and the background processes e^{+}e^{-}→γ_{ISR}J/ψ→γ_{ISR}μ^{+}μ^{-} and e^{+}e^{-}→γ_{ISR}μ^{+}μ^{-} is observed by combining all the data samples. The χ_{c1}(1P) signal is observed with a significance of 5.1σ. This is the first observation of a C-even state directly produced in e^{+}e^{-} annihilation. The electronic width of the χ_{c1}(1P) resonance is determined to be Γ_{ee}=(0.12_{-0.08}^{+0.13}) eV, which is of the same order of magnitude as theoretical calculations.
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Evidence for a Neutral Near-Threshold Structure in the K_{S}^{0} Recoil-Mass Spectra in e^{+}e^{-}→K_{S}^{0}D_{s}^{+}D^{*-} and e^{+}e^{-}→K_{S}^{0}D_{s}^{*+}D^{-}. PHYSICAL REVIEW LETTERS 2022; 129:112003. [PMID: 36154413 DOI: 10.1103/physrevlett.129.112003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 06/17/2022] [Accepted: 06/30/2022] [Indexed: 06/16/2023]
Abstract
We study the processes e^{+}e^{-}→K_{S}^{0}D_{s}^{+}D^{*-} and e^{+}e^{-}→K_{S}^{0}D_{s}^{*+}D^{-}, as well as their charge conjugated processes, at five center-of-mass energies between 4.628 and 4.699 GeV, using data samples corresponding to an integrated luminosity of 3.8 fb^{-1} collected by the BESIII detector at the BEPCII storage ring. Based on a partial reconstruction technique, we find evidence of a structure near the thresholds for D_{s}^{+}D^{*-} and D_{s}^{*+}D^{-} production in the K_{S}^{0} recoil-mass spectrum, which we refer to as the Z_{cs}(3985)^{0}. Fitting with a Breit-Wigner line shape, we find the mass of the structure to be (3992.2±1.7±1.6) MeV/c^{2} and the width to be (7.7_{-3.8}^{+4.1}±4.3) MeV, where the first uncertainties are statistical and the second are systematic. The significance of the Z_{cs}(3985)^{0} signal is found to be 4.6σ including both the statistical and systematic uncertainty. We report the Born cross section multiplied by the branching fraction at different energy points. The mass of the Z_{cs}(3985)^{0} is close to that of the Z_{cs}(3985)^{+}. Assuming SU(3) symmetry, the cross section of the neutral channel is consistent with that of the charged one. Hence, we conclude that the Z_{cs}(3985)^{0} is the isospin partner of the Z_{cs}(3985)^{+}.
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Observation of Resonance Structures in e^{+}e^{-}→π^{+}π^{-}ψ_{2}(3823) and Mass Measurement of ψ_{2}(3823). PHYSICAL REVIEW LETTERS 2022; 129:102003. [PMID: 36112441 DOI: 10.1103/physrevlett.129.102003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 07/21/2022] [Accepted: 08/09/2022] [Indexed: 06/15/2023]
Abstract
Using a data sample corresponding to an integrated luminosity of 11.3 fb^{-1} collected at center-of-mass energies from 4.23 to 4.70 GeV with the BESIII detector, we measure the product of the e^{+}e^{-}→π^{+}π^{-}ψ_{2}(3823) cross section and the branching fraction B[ψ_{2}(3823)→γχ_{c1}]. For the first time, resonance structure is observed in the cross section line shape of e^{+}e^{-}→π^{+}π^{-}ψ_{2}(3823) with significances exceeding 5σ. A fit to data with two coherent Breit-Wigner resonances modeling the sqrt[s]-dependent cross section yields M(R_{1})=4406.9±17.2±4.5 MeV/c^{2}, Γ(R_{1})=128.1±37.2±2.3 MeV, and M(R_{2})=4647.9±8.6±0.8 MeV/c^{2}, Γ(R_{2})=33.1±18.6±4.1 MeV. Though weakly disfavored by the data, a single resonance with M(R)=4417.5±26.2±3.5 MeV/c^{2}, Γ(R)=245±48±13 MeV is also possible to interpret data. This observation deepens our understanding of the nature of the vector charmoniumlike states. The mass of the ψ_{2}(3823) state is measured as (3823.12±0.43±0.13) MeV/c^{2}, which is the most precise measurement to date.
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Observation of a State X(2600) in the π^{+}π^{-}η' System in the Process J/ψ→γπ^{+}π^{-}η'. PHYSICAL REVIEW LETTERS 2022; 129:042001. [PMID: 35939017 DOI: 10.1103/physrevlett.129.042001] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 06/24/2022] [Indexed: 06/15/2023]
Abstract
Based on (10087±44)×10^{6} J/ψ events collected with the BESIII detector, the process J/ψ→γπ^{+}π^{-}η^{'} is studied using two largest decay channels of the η^{'} meson, η^{'}→γπ^{+}π^{-} and η^{'}→ηπ^{+}π^{-}, η→γγ. A new resonance, which we denote as the X(2600), is observed with a statistical significance larger than 20σ in the π^{+}π^{-}η^{'} invariant mass spectrum, and it has a connection to a structure around 1.5 GeV/c^{2} in the π^{+}π^{-} invariant mass spectrum. A simultaneous fit on the π^{+}π^{-}η^{'} and π^{+}π^{-} invariant mass spectra with the two η^{'} decay modes indicates that the mass and width of the X(2600) state are 2618.3±2.0_{-1.4}^{+16.3} MeV/c^{2} and 195±5_{-17}^{+26} MeV, where the first uncertainties are statistical, and the second systematic.
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Observation of J/ψ Electromagnetic Dalitz Decays to X(1835), X(2120), and X(2370). PHYSICAL REVIEW LETTERS 2022; 129:022002. [PMID: 35867444 DOI: 10.1103/physrevlett.129.022002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 04/07/2022] [Accepted: 06/08/2022] [Indexed: 06/15/2023]
Abstract
Using a sample of about 10^{10} J/ψ events collected at a center-of-mass energy sqrt[s]=3.097 GeV with the BESIII detector, the electromagnetic Dalitz decays J/ψ→e^{+}e^{-}π^{+}π^{-}η^{'}, with η^{'}→γπ^{+}π^{-} and η^{'}→π^{+}π^{-}η, have been studied. The decay J/ψ→e^{+}e^{-}X(1835) is observed with a significance of 15σ, and also an e^{+}e^{-} invariant-mass dependent transition form factor of J/ψ→e^{+}e^{-}X(1835) is presented for the first time. The intermediate states X(2120) and X(2370) are also observed in the π^{+}π^{-}η^{'} invariant-mass spectrum with significances of 5.3σ and 7.3σ. The corresponding product branching fractions for J/ψ→e^{+}e^{-}X, X→π^{+}π^{-}η^{'} [X=X(1835), X(2120), and X(2370)] are reported.
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[The preference for Front-of-Pack Labeling and its association with the understanding of Nutrition Facts Panel among residents aged 18 to 70: results of a survey in 6 provinces of China]. ZHONGHUA YU FANG YI XUE ZA ZHI [CHINESE JOURNAL OF PREVENTIVE MEDICINE] 2022; 56:952-959. [PMID: 35899348 DOI: 10.3760/cma.j.cn112150-20211102-01013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Objective: To investigate the preference for Front-of-Pack Labeling (FOP) and its association with the understanding of the Nutrition Facts Panel among Chinese residents. Methods: A multi-stage sampling strategy was adopted to select 3 002 people aged between 18 and 70 years old from the eastern region of China (Beijing, Jiangsu Province, Guangdong Province), the northeast region (Heilongjiang Province), the central region (Henan Province) and the western region (Sichuan Province) from July 2020 to March 2021. Socio-demographic characteristics of participants and their understanding of the Nutrition Facts Panel and preference for FOP were collected. The χ² test was conducted to compare the preference for FOP in different groups of population, and multivariate logistic regression was used to analyze the association between the preference for FOP and the understanding of the Nutrition Facts Panel. Results: The mean age of 3 002 participants was (42.3±13.4) years, of which 1 914 (63.8%) were females and 69.3% could not understand the Nutrition Facts Panel. About 2 458 respondents (81.9%) suggested that FOP could be promoted. The top three nutrients that should be labeled were sugar (68.4%), salt (68.2%) and total fat (62.4%). The number of participants who believed that the Multiple Traffic Lights (MTL) could be easier to help consumers to quickly choose healthy food, attract attention and provide the most needed information was 1 064 (35.4%), 1 026 (34.2%) and 1 140 (38.0%), respectively. The multivariate logistic regression analysis showed that, compared with the Guideline Daily Amount (GDA) system, participants who could not understand the Nutrition Facts Panel preferred (1) Nutri-Score, Warning labels, and Health logos: Smart Choice in terms of"Which format of FOP could quickly help you choose food more easily?"[OR (95%CI): 2.21 (1.62-3.02), 1.64 (1.22-2.22), 1.79 (1.31-2.45), respectively]; (2) Nutri-Score, Warning labels, and Health logos: Smart Choice in terms of"Which format of FOP could attract your attention the most?"[OR (95%CI): 2.62 (1.92-3.59), 1.96 (1.45-2.66), 2.25 (1.66-3.04), respectively]; and (3) Nutri-Score, Warning labels, and Health logos: Smart Choice in terms of"Which format of FOP could provide you with the most needed information?"[OR (95%CI): 2.33 (1.70-3.21), 2.21 (1.66-2.95), 2.01 (1.50-2.71), respectively]. Conclusion: The residents from six provinces in China have a supportive attitude towards FOP. The interpretive FOP with color information, specific nutrient information and summary indicator can be launched. The nutrition information of sugar, salt and total fat could be prioritized to be labeled on the FOP.
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[Research progress of vascular smooth muscle cells phenotypic switching in Marfan syndrome]. ZHONGHUA XIN XUE GUAN BING ZA ZHI 2022; 50:410-414. [PMID: 35399040 DOI: 10.3760/cma.j.cn112148-20210412-00324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
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Observation of the Singly Cabibbo Suppressed Decay Λ_{c}^{+}→nπ^{+}. PHYSICAL REVIEW LETTERS 2022; 128:142001. [PMID: 35476477 DOI: 10.1103/physrevlett.128.142001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 02/05/2022] [Accepted: 03/01/2022] [Indexed: 06/14/2023]
Abstract
The singly Cabibbo-suppressed decay Λ_{c}^{+}→nπ^{+} is observed for the first time with a statistical significance of 7.3σ by using 3.9 fb^{-1} of e^{+}e^{-} collision data collected at center-of-mass energies between 4.612 and 4.699 GeV with the BESIII detector at BEPCII. The branching fraction of Λ_{c}^{+}→nπ^{+} is measured to be (6.6±1.2_{stat}±0.4_{syst})×10^{-4}. By taking the upper limit of branching fractions of Λ_{c}^{+}→pπ^{0} from the Belle experiment, the ratio of branching fractions between Λ_{c}^{+}→nπ^{+} and Λ_{c}^{+}→pπ^{0} is calculated to be larger than 7.2 at the 90% confidence level, which disagrees with most predictions of the available phenomenological models. In addition, the branching fractions of the Cabibbo-favored decays Λ_{c}^{+}→Λπ^{+} and Λ_{c}^{+}→Σ^{0}π^{+} are measured to be (1.31±0.08_{stat}±0.05_{syst})×10^{-2} and (1.22±0.08_{stat}±0.07_{syst})×10^{-2}, respectively, which are consistent with previous results.
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