Determination of Spin-Parity Quantum Numbers of X(2370) as 0^{-+} from J/ψ→γK_{S}^{0}K_{S}^{0}η^{'}

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.

[Neoadjuvant strategy for locally advanced colorectal cancer based organ preservation]

Neoadjuvant therapy for locally advanced colorectal cancer has made great progress in the past 20 years, but there are still limitations such as side effects, organ dysfunction and unsatisfactory control of metastasis. In recent years, with the improvement of surgical techniques and further development of molecular research, how to further improve local control, reduce distant metastasis, and even avoid surgery according to clinical remission to achieve organ preservation, is the current demand and research goal. With the advancement of molecular research, colorectal cancer has different treatment strategies based on microsatellite status. For patients with microsatellite instability locally advanced colorectal cancer, immune checkpoint inhibitor therapy significantly increased the pathologic complete response rate, reduced the incidence of adverse events and improved organ function compared with conventional chemoradiotherapy. For patients with microsatellite stable locally advanced colon cancer, neoadjuvant therapy is still in the exploratory stage. The standard of care is surgery combined with perioperative chemotherapy. For microsatellite stable locally advanced rectal cancer, the complete response rate is improved by enhancing neoadjuvant therapy, which helps to preserve organs. On the other hand, selective radiotherapy preserves organ function and improves quality of life. This article reviews the neoadjuvant treatment strategies for locally advanced colorectal cancer based on organ-sparing strategies.

Observation of Structures in the Processes e^{+}e^{-}→ωχ_{c1} and ωχ_{c2}

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.

Coupled-Channel Analysis of the χ_{c1}(3872) Line Shape with BESIII Data

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.

Observation of the Anomalous Shape of X(1840) in J/ψ→γ3(π^{+}π^{-}) Indicating a Second Resonance Near pp[over ¯] Threshold

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.

Study of the f_{0}(980) and f_{0}(500) Scalar Mesons through the Decay D_{s}^{+}→π^{+}π^{-}e^{+}ν_{e}

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.

Observation of D^{+}→K_{S}^{0}a_{0}(980)^{+} in the Amplitude Analysis of D^{+}→K_{S}^{0}π^{+}η

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.

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}

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 Collapse

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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

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.

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

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.

Determination of the Σ^{+} Timelike Electromagnetic Form Factors

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.

[Global trends in the incidence and prevalence of pneumoconiosis in 204 countries/territories from 1990 to 2019]

Objective: To analyze the changing trend of incidence and prevalence of pneumoconiosis globally, and provide scientific basis for the formulation of health policy. Methods: In June 2022, through the Global Health Data exchange (GHDx) query tool (http: //ghdx.healthdata.org/gbd-results-tool) , the pneumoconiosis incidence and prevalence data was downloaded and organized. Estimated annual percentage change (EAPC) and age-standardized rate (ASR) were used to estimate the trends of pneumoconiosis from 1990 to 2019. EAPC was estimated by linear regression model based on ASR. Results: The overall ASR of the incidence and prevalence of pneumoconiosis decreased from 1990 to 2019, and their EAPCs were-0.85% (95%CI: -1.11%--0.60%) and -0.78% (95%CI: -1.08%--0.49%) . Over the past 30 years, the incidence and prevalence of pneumoconiosis in all SDI areas showed decreasing trends, especially in high SDI areas, their EAPCs were -1.46% (95%CI: -1.76%--1.15%) and -1.99% (95%CI: -2.44%--1.53%) . 110 countries/areas showed increasing trends in age standardized incidence rate (ASIR) , with Iran and Georgia showing the most pronounced upward trend, their EAPCs were 5.32% (95%CI: 4.43%-6.22%) and 4.39% (95%CI: 3.81%-4.97%) . 125 countries/areas showed anincreasing trends in prevalence ASR, with Iran had the fastest rise in prevalence (EAPC=6.40%, 95%CI: 5.33%-7.49%) . Conclusion: Although decreasing trends in the burden of pneumoconiosis are observed globally from 1990 to 2019, but the burden of pneumoconiosis in low-and middle-income countries or regions are still heavy. We need more effective strategies to prevent and reduce the burden of pneumoconiosis.

First Measurement of the Decay Asymmetry in the Pure W-Boson-Exchange Decay Λ_{c}^{+}→Ξ^{0}K^{+}

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.

Test of CP Symmetry in Hyperon to Neutron Decays

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.

Measurement of Energy-Dependent Pair-Production Cross Section and Electromagnetic Form Factors of a Charmed Baryon

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.

Determination of Spin-Parity Quantum Numbers for the Narrow Structure near the pΛ[over ¯] Threshold in e^{+}e^{-}→pK^{-}Λ[over ¯]+c.c

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}.

Precise Measurement of the e^{+}e^{-}→D_{s}^{*+}D_{s}^{*-} Cross Sections at Center-of-Mass Energies from Threshold to 4.95 GeV

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.

First Experimental Study of the Purely Leptonic Decay D_{s}^{*+}→e^{+}ν_{e}

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.

Search for Λ[over ¯]-Λ Baryon-Number-Violating Oscillations in the Decay J/ψ→pK^{-}Λ[over ¯]+c.c

We report on the first search for Λ[over ¯]-Λ oscillations in the decay J/ψ→pK^{-}Λ[over ¯]+c.c. by analyzing 1.31×10^{9}  J/ψ events accumulated with the BESIII detector at the BEPCII collider. The J/ψ events are produced using e^{+}e^{-} collisions at a center of mass energy sqrt[s]=3.097  GeV. No evidence for hyperon oscillations is observed. The upper limit for the oscillation rate of Λ[over ¯] to Λ hyperons is determined to be P(Λ)=[B(J/ψ→pK^{-}Λ+c.c.)/B(J/ψ→pK^{-}Λ[over ¯]+c.c.)]<4.4×10^{-6} corresponding to an oscillation parameter δm_{ΛΛ[over ¯]} of less than 3.8×10^{-18}  GeV at the 90% confidence level.

[Effect of preimplantation genetic testing for aneuploidies on pregnancy outcome in patients with unexplained recurrent spontaneous abortion]

Objective: To investigate the effect of preimplantation genetic testing for aneuploidies (PGT-A) on pregnancy outcome and perinatal outcome of single live birth in patients with unexplained recurrent spontaneous abortion (URSA). Methods: The clinical data of 351 cycles of the first transfer of a blastocyst through whole embryo freezing in the Reproductive Center of the Third Affiliated Hospital of Zhengzhou University from 2019 to 2021 were retrospectively analyzed. According to whether PGT-A was performed before the transfer, the patients were divided into two groups: the PGT-A group (160 cycles) and the control group (191 cycles) were treated with in vitro fertilization/intracytoplasmic sperm microinjection (IVF/ICSI). To adjust for confounding factors, propensity score matching (PSM) was carried out in a 1∶1 ratio between the two groups of patients. After matching, 98 patients in the PGT-A group and 98 patients in the control group were compared for pregnancy outcome and perinatal outcome of singleton live births. Results: Before PSM, the female age in the PGT-A group was (33.6±4.0) years, lower than that in the control group (34.5±4.5) years (P=0.049). Male age in the PGT-A group was (33.6±4.1) years, lower than that in the control group (35.3±5.1) years (P<0.001). There were statistically significant differences between the two groups in infertility factors, female body mass index (BMI), years of infertility, number of spontaneous abortions, basal follicle stimulating hormone (FSH), endometrial thickness on the day of transfer and the percentage of high-quality blastocysts (all P values<0.05); After PSM, there was a statistically significant difference in fertilization methods and infertility factors between the two groups (P<0.05), while other differences were not statistically significant (all P values>0.05); There were statistically significant differences between the two groups in implant rate [63.3% (62 cycles) vs. 49.0% (48 cycles), P=0.044], clinical pregnancy rate [63.3% (62 cycles) vs. 49.0% (48 cycles), P=0.044], and live birth rate [42.9% (42 cycles) vs. 28.6% (28 cycles), P=0.037]. There was no statistically significant difference in perinatal outcomes between the PGT-A group and the control group in obtaining single birth live births (P>0.05). Conclusion: Compared with conventional IVF/ICSI assisted pregnancy, PGT-A assisted pregnancy significantly improves implantation rate, clinical pregnancy rate, and live birth rate in URSA patients. PGT-A improves the pregnancy outcomes in URSA patients but not perinatal outcomes in patients with singleton live births.

[The effect of chronic endometritis on the clinical outcomes of patients with failure of first embryo transfer]

Objective: To investigate the effect of chronic endometritis (CE) on the clinical outcomes of patients with failure of first embryo transfer. Methods: A total of 5 605 cycles of frozen-thawed single blastocyst transfer in the reproductive center of the Third Affiliated Hospital of Zhengzhou University from January 2017 to June 2021 were retrospectively collected. After the failure of first embryo transfer, all patients underwent hysteroscopy, and when necessary, endometrial pathology and immunohistochemistry were combined to diagnose CE. Patients were divided into two groups: non-CE group (5 033 cycles) and CE treatment group (572 cycles). The main outcome was live birth rate and the secondary outcomes included clinical pregnancy rate and early abortion rate. The quantitative data were represented by Median (Q1, Q3). The rank sum test was used for comparison between groups. The factors related to live birth rate were analyzed by binary logistic regression model. Results: The incidence of CE was 10.21% (572 cycles) in patients with the failure of first embryo transfer. The maternal age in the non-CE group was 31.0 (29.0, 34.0) years old, and that in the CE treatment group was 31.0 (29.0, 34.0) years old (P<0.001). There was a statistically significant difference in endometrial preparation between the two groups (P=0.010). The endometrial thickness in the CE group was 9.0 (8.2, 10.3) mm on progesterone transformation day, which was higher than that of [9.5 (8.6, 11.0) mm] in the non-CE group (P<0.001). There was no significant difference in clinical pregnancy rate (60.3% (3 035 cycles) vs 63.1% (361 cycles), P=0.193), early abortion rate (17.1% (520 cycles) vs 20.5% (74 cycles), P=0.112) and live birth rate (49.2% (2 477 cycles) vs 49.3% (282 cycles), P=0.969) between the non-CE group and the CE treatment group. The maternal age, endometrial thickness on progesterone transformation day and blastocyst grade were related factors of the live birth rate, and the OR(95%CI) were 0.94 (0.93-0.96), 1.10 (1.06-1.14) and 2.07 (1.84-2.32)), respectively (all P<0.001). Compared with the non-CE group, the CE treatment group did not affect the live birth rate after transplantation, the aOR (95%CI) was 0.99 (0.82-1.18), P=0.882. Conclusions: For patients who underwent the failure of first embryo transfer, hysteroscopy is recommended before single frozen blastocyst transfer, and if necessary, combined with immunohistochemical screening for CE. After standardized treatment, CE patients could obtain similar clinical pregnancy rate, early miscarriage rate and live birth rate as non-CE patients.

First Study of Reaction Ξ^{0}n→Ξ^{-}p Using Ξ^{0}-Nucleus Scattering at an Electron-Positron Collider

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.

[Predictive value of the triglyceride-glucose index on atrial fibrillation recurrence after valvular surgery with concurrent Cox-maze Ⅳ ablation]

Objective: To investigate the predictive value of preoperative triglyceride-glucose (TyG) index on atrial fibrillation recurrence after valvular surgery with concurrent Cox-maze Ⅳ ablation. Methods: The data of the patients who underwent valvular surgery with concurrent Cox-maze Ⅳ ablation from June 2017 to May 2022 in the Department of Cardiac Surgery, Beijing Anzhen Hospital were retrospectively collected, and the patients were divided into the recurrence group and non-recurrence group. Baseline clinical data and results of laboratory tests were collected and TyG index was calculated. The univariate and multivariate Cox proportional regression analysis were used to explore the risk factors of atrial fibrillation recurrence after Cox-maze Ⅳ ablation. The value of TyG index in predicting atrial fibrillation recurrence was obtained by plotting receiver operating characteristic (ROC) curve. Results: A total of 424 patients were in the final analysis, including 300 males and 124 females, with an average age of (58.2±13.4) years. The median follow-up time was 32.7 months (17.3-49.6 months). There were 117 and 307 patients in the recurrence and non-recurrence groups, respectively. Compared with the non-recurrence group, the TyG index in the recurrence group was higher (9.21±0.38 vs 8.34±0.72, P=0.011). The multivariate Cox regression analysis showed that TyG index (HR=2.021, 95%CI: 1.374-3.245, P<0.001), C-reactive protein level (HR=1.127, 95%CI: 1.007-1.535, P=0.026) and mitral stenosis (HR=1.038, 95%CI: 1.004-1.483, P<0.001) were risk factors for atrial fibrillation recurrence after Cox-maze Ⅳ ablation. In addition, TyG index was a predictor of atrial fibrillation recurrence according to ROC curve analysis [area under the curve (AUC)=0.847, 95%CI: 0.796-0.871, P<0.001]. Conclusion: The TyG index is an effective indicator to predict the recurrence of atrial fibrillation after valvular surgery with concurrent Cox-maze Ⅳ ablation.

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

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.

Improved Measurement of the Evolution of the Reactor Antineutrino Flux and Spectrum at Daya Bay

Reactor neutrino experiments play a crucial role in advancing our knowledge of neutrinos. In this Letter, the evolution of the flux and spectrum as a function of the reactor isotopic content is reported in terms of the inverse-beta-decay yield at Daya Bay with 1958 days of data and improved systematic uncertainties. These measurements are compared with two signature model predictions: the Huber-Mueller model based on the conversion method and the SM2018 model based on the summation method. The measured average flux and spectrum, as well as the flux evolution with the ^{239}Pu isotopic fraction, are inconsistent with the predictions of the Huber-Mueller model. In contrast, the SM2018 model is shown to agree with the average flux and its evolution but fails to describe the energy spectrum. Altering the predicted inverse-beta-decay spectrum from ^{239}Pu fission does not improve the agreement with the measurement for either model. The models can be brought into better agreement with the measurements if either the predicted spectrum due to ^{235}U fission is changed or the predicted ^{235}U, ^{238}U, ^{239}Pu, and ^{241}Pu spectra are changed in equal measure.

Precision Measurement of the Decay Σ^{+}→pγ in the Process J/ψ→Σ^{+}Σ[over ¯]^{-}

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.

[Prognostic factors for non-small cell lung cancer patients with central nervous system metastasis with positive driver genes]

Objective: To investigate the prognostic factors of patients with central nervous system (CNS) metastatic non-small cell lung cancer (NSCLC) with positive driver genes. Methods: The clinical data of 103 patients with CNS metastatic NSCLC admitted to Beijing Tongren Hospital from January 2016 to December 2020 were retrospectively analyzed, and the patients were divided into positive driver gene group (patients with driver genes mutation and receiving corresponding targeted therapy) and negative driver gene group. Cox univariate and multivariate regression analyses were performed to identify the factors affecting patients' prognosis, and the receiver operating characteristic curve (ROC) was used to compare the predictive ability of 4 scoring systems [recursive partitioning analysis (RPA) classes, diagnosis-specific graded prognostic assessment (DS-GPA) index, basic score for brain metastasesn (BS-BM) and (lung-molecular graded prognostic assessment (lung-mol GPA)]on patients' prognosis. Results: Among the 103 patients, 48 were males and 55 were females, and aged (64.6±9.7) years old. The median survival time of the 103 patients was 24.0 (95%CI: 20.0-28.0) months, the median survival time of the 59 patients in the positive driver gene group was 33.0 (95%CI: 23.4-42.6) months, the median survival time of the 44 patients in the negative driver gene group was 17.0 (95%CI: 14.4-19.6) months, and the difference was statistically significant (χ²=24.69, P<0.001). The results of Cox multivariate analysis showed that the negative driver genes (HR=3.788, 95%CI: 1.951-7.301, P=0.001), Karnofsky performance status (KPS) score<70 (HR=2.613, 95%CI: 1.185-5.761, P=0.017) and neutrophil-to-lymphocyte ratio (NLR)>3.22 (HR=2.714, 95%CI: 1.157-6.365, P=0.022) were independent risk factors affecting the prognosis of patients with CNS metastatic NSCLC. KPS score<70 (HR=3.719, 95%CI: 1.165-11.876, P=0.027) and no radiotherapy (HR=2.032, 95%CI: 1.033-11.364, P=0.041) were independent risk factors affecting the prognosis of patients with CNS metastatic NSCLC with positive driver genes. ROC curve analysis showed that the area under curve (AUC) value of lung-mol GPA was the highest among the 4 scoring systems (AUC=0.843, 95%CI: 0.731-0.956, P<0.001), and the AUC value of the lung-mol GPA combined scoring system (AUC=0.904, 95%CI: 0.816-0.991, P<0.001) was higher than lung-mol GPA. Conclusions: A low KPS score and no cranial radiation therapy are independent risk factors for the prognosis of patients with CNS metastatic NSCLC with positive driver genes; the lung-mol GPA joint scoring system is more conducive to the prognostic assessment of patients with CNS metastatic NSCLC with positive driver genes.

Precision Measurement of Reactor Antineutrino Oscillation at Kilometer-Scale Baselines by Daya Bay

We present a new determination of the smallest neutrino mixing angle θ_{13} and the mass-squared difference Δm_{32}^{2} using a final sample of 5.55×10^{6} inverse beta-decay (IBD) candidates with the final-state neutron captured on gadolinium. This sample is selected from the complete dataset obtained by the Daya Bay reactor neutrino experiment in 3158 days of operation. Compared to the previous Daya Bay results, selection of IBD candidates has been optimized, energy calibration refined, and treatment of backgrounds further improved. The resulting oscillation parameters are sin^{2}2θ_{13}=0.0851±0.0024, Δm_{32}^{2}=(2.466±0.060)×10^{-3}  eV^{2} for the normal mass ordering or Δm_{32}^{2}=-(2.571±0.060)×10^{-3}  eV^{2} for the inverted mass ordering.

Measurements of the Electric and Magnetic Form Factors of the Neutron for Timelike Momentum Transfer

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.

Observation of a New X(3872) Production Process e^{+}e^{-}→ωX(3872)

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.

[Application of augmented reality navigation in laparoscopic and robot-assisted liver surgery]

In recent years, laparoscopic surgery and robotic surgery have been widely used, and various intraoperative image navigation systems have also developed rapidly. However, the liver itself has a complex vessel and duct system, which increase the difficulty of liver surgery. The augmented reality image navigation system combines the three-dimensional reconstructed image of the liver with the real liver anatomy, which presents the specific relationship between the tumor location and the surrounding vessels for the surgeon. Compared with other intraoperative image navigation methods, augmented reality has its unique advantages. This paper provides an overview of current advances in registration technology in augmented reality image navigation system, and focuses on its applications in liver surgery, including laparoscopic surgery and robotic surgery. Finally, the technological problems and difficulties still faced at present are summarized, and future directions worth studying in this field are proposed.

Observation of Three Charmoniumlike States with J^{PC}=1^{--} in e^{+}e^{-}→D^{*0}D^{*-}π^{+}

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.

Evidence for the Cusp Effect in η' Decays into ηπ^{0}π^{0}

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.

Co-Dissolved Isostructural Polyoxovanadates to Construct Single-Atom-Site Catalysts for Efficient CO2 Photoreduction

We explored a co-dissolved strategy to embed mono-dispersed Pt center into V₂ O₅ support via dissolving [PtV₉ O₂₈ ]^7- into [V₁₀ O₂₈ ]^6- aqueous solution. The uniform dispersion of [PtV₉ O₂₈ ]^7- in [V₁₀ O₂₈ ]^6- solution allows [PtV₉ O₂₈ ]^7- to be surrounded by [V₁₀ O₂₈ ]^6- clusters via a freeze-drying process. The V centers in both [PtV₉ O₂₈ ]^7- and [V₁₀ O₂₈ ]^6- were converted into V₂ O₅ via a calcination process to stabilize Pt center. These double separations can effectively prevent the Pt center agglomeration during the high-temperature conversion process, and achieve 100 % utilization of Pt in [PtV₉ O₂₈ ]^7- . The resulting Pt-V₂ O₅ single-atom-site catalysts exhibit a CH₄ yield of 247.6 μmol g^-1  h^-1 , 25 times higher than that of Pt nanoparticle on the V₂ O₅ support, which was accompanied by the lactic acid photooxidation to form pyruvic acid. Systematical investigations on this unambiguous structure demonstrate an important role of Pt-O atomic pair synergy for highly efficient CO₂ photoreduction.

[The risk prediction value of paraquat poisoning dose, urine protein and myocardial enzymes]

Objective: To explore the value of paraquat (PQ) intake, urine protein and myocardial enzyme indexes in judging the prognosis of patients with acute PQ poisoning. Methods: From September to December 2021, all 201 patients with acute PQ poisoning admitted to Guangzhou Twelfth People's Hospital from January 2010 to December 2019 were selected as the research objects. Based on follow-up results 60 days after poisoning, the research objects were divided into survival group (n=78) and death group (n=123) . The differences in information about poisoning, treatment plan, PQ intake, urine protein, creatine kinase, creatine kinase isoenzyme, lactate dehydrogenase, and α-hydroxybutyrate dehydrogenase between the two groups of patients were compared and analyzed. Logistic regression and Cox regression were used to analyze the correlation between poisoning outcome and PQ intake, urine protein and myocardial enzymes. ROC curve and principal component analysis were used to explore high-efficiency indicators for predicting the outcome of acute PQ poisoning. Results: The PQ intake[50 (20, 100) ml], urine protein (total rank 15570.50) , creatine kinase[ (336.36±261.96) U/L], creatine kinase isoenzyme[ (43.91±43.74) U/L], lactate dehydrogenase [ (346.01±196.50) U/L], α-hydroxybutyrate dehydrogenase content[ (271.23±11.92) U/L] of patients in the death group were all higher than the survival group[15 (10, 20) ml, 4730.50, (187.78±178.06) U/L, (18.88±15.50) U/L, (190.92±60.50) U/L, (152.60±48.34) U/L, respectively] (P<0.05) . The outcome of acute PQ poisoning was positively correlated with PQ intake, urine protein, creatine kinase, creatine kinase isoenzyme, lactate dehydrogenase, and α-hydroxybutyrate dehydrogenase (P<0.05) . Multivariate logistic regression and multivariate Cox regression analysis showed that creatine kinase, creatine kinase isoenzyme, lactate dehydrogenase and α-hydroxybutyrate dehydrogenase was positively correlated with the prognosis of patients with acute PQ poisoning (P<0.05) . ROC curve analysis and principal component analysis showed that the combined indexes of PQ intake, urine protein and myocardial enzymes had the highest efficacy and weight in judging the prognosis of patients (AUC=0.91, weight coefficient=0.19, sensitivity=0.76, specificity=0.89) . When the combined score was ≥4, the probability of accurately predicting the death of patients was as high as 91% (positive predictive value=0.91) . Conclusion: PQ intake, urine protein combined with creatine kinase, creatine kinase isoenzyme, lactate dehydrogenase, and α-hydroxybutyrate dehydrogenase has high value in predicting the prognosis of patients with acute PQ poisoning.

Study of the Semileptonic Decay Λ_{c}^{+}→Λe^{+}ν_{e}

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}}}.

[The effect of human chorionic gonadotropin day serum progesterone level on the live birth rate of fresh embryo transfer with GnRH antagonist protocols]

Objective: To investigate the effect of human chorionic gonadotropin (HCG)day serum progesterone (P) level on the live birth rate (LBR) of fresh embryo transfer with GnRH antagonist protocols. Methods: Patients who underwent the first IVF/ICSI in the Reproductive Center of the Third Affiliated Hospital of Zhengzhou University from January 2018 to December 2020 were included for analysis. The patients with normal ovarian response with GnRH antagonist protocols were included (n=765). The receiver operating characteristic curve (ROC) was used to select the optimal cut-off value of serum P on HCG day (0.83 μg/L), and the included cycles were divided into two groups: P<0.83 μg/L (n=444) and P≥0.83 μg/L (n=321). The primary outcome measure was LBR. Secondary outcome measures included clinical pregnancy rate (CPR) and early miscarriage rate. The difference of the above indexes between the two groups was compared. Multivariate logistic regression model was used to analyze the effect of serum P level on LBR in fresh embryo transfer cycles. Results: The maternal ages in P<0.83 μg/L group and P≥0.83 μg/L group were (32.40±5.49) years and (32.53±5.51) yeas, respectively. The paternal ages were (33.35±6.34) years and (33.43±6.38) years, respectively of which, the difference was not statistically significant (P>0.05). The CPR in the P<0.83 μg/L group was 45.9% (n=204), which was significantly higher than that in the P≥0.83 μg/L group (37.1%) (n=119) (P=0.014). There was no significant difference in the early miscarriage rate between the two groups [14.2% (n=29) vs 14.3% (n=17), P=0.986]. The LBR in the P<0.83 μg/L group was significantly higher than that in the P≥0.83 μg/L group [36.3% (n=161) vs 28.0% (n=90), P=0.017]. By multivariate logistic regression model analysis, the maternal age, type of embryo transferred, number of embryos transferred, endometrial thickness on HCG day and serum P level on HCG day were independent risk factors of LBR. The adjust OR(95%CI) were 0.91(0.88-0.94), 2.36(1.04-5.35), 1.84(1.14-2.95), 1.16(1.07-1.25)and 0.63(0.44-0.89), all P<0.05. Conclusion: When the GnRH antagonist protocol is applied in the normal ovarian response population, as the serum P on the HCG trigger day≥0.83 μg/L, the CPR and LBR of fresh embryo transfer are decreased.

Measurement of the Absolute Branching Fraction and Decay Asymmetry of Λ→nγ

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}.

[The purchase behavior of prepackaged food and its determinants among primary and middle school students in 6 provinces of China]

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.

Observation of an Isoscalar Resonance with Exotic J^{PC}=1^{-+} Quantum Numbers in J/ψ→γηη^{'}

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.

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

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})%.

[Association between the awareness of Nutrition Facts Panel and prepackaged food purchase behavior among residents]

Objective: To explore the association between the cognition of Nutrition Facts Panel and prepackaged food purchase behavior among residents in six provinces in China. Methods: Using a multi-stage sampling method, 3 002 adults aged 18-70 were selected from the western region (Sichuan), eastern region (Guangdong, Jiangsu, Beijing), central region (Henan), and northeastern region (Heilongjiang) of China from July 2020 to March 2021. Socio-demographic characteristics of participants and their cognition of Nutrition Facts Panel and prepackaged food purchase behavior were collected through questionnaire. A multivariate binary logistic regression model was used to analyze the association between cognition of Nutrition Facts Panel and prepackaged food purchase behavior. Results: The age of 3 002 subjects was (42.3±13.4) years, among which 63.8% (1 914) were female, 66.7% knew the Nutrition Facts Panel, 49.8% would read it when purchasing, 30.7% could understand it, and 56.6% (1 699) bought prepackaged food more than once a week. The results of multivariate analysis showed that after adjusting for relevant confounding factors, compared with the participants knowing but not reading the Nutrition Facts Panel, the group knowing and reading was more likely to buy 11 types of prepackaged food at least once a week (all P<0.05). Compared with the participants reading but not understanding the Nutrition Facts Panel, the group reading and understanding was less likely to buy 11 types of prepackaged food at least once a week (all P<0.05). Conclusion: There was a correlation between cognition of Nutrition Facts Panel and prepackaged food purchase behavior among residents.

Precise Measurements of Decay Parameters and CP Asymmetry with Entangled Λ-Λ[over ¯] Pairs

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.

First Observation of the Direct Production of the χ_{c1} in e^{+}e^{-} Annihilation

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.

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^{-}

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)^{+}.

Observation of Resonance Structures in e^{+}e^{-}→π^{+}π^{-}ψ_{2}(3823) and Mass Measurement of ψ_{2}(3823)

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.