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.

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.

[Association between obesity and risk for all-cause mortality in patients with type 2 diabetes]

Objective: To investigate the association between obesity and the risk for all-cause mortality in type 2 diabetes (T2DM) patients. Methods: The participants were from a rural community-based T2DM patient cohort in Zhejiang Province. The study used the data collected from baseline survey in 2016 and follow-up until December 31, 2021. A total of 10 310 participants were included, excluding those who were lost in follow-up or had incomplete data in follow-up. According to BMI and waist circumference, the study subjects were divided into 6 groups: low body weight, normal body weight, simple abdominal obesity, simple body obesity, complex overweight and complex obesity. Cox proportional hazards regression model was used to analyze hazard ratios (HRs) of all-cause mortality and their 95%CIs in T2DM patients with different obesity status. Results: The cumulative follow-up period was 57 049.47 person-years with an average follow-up of (5.53±0.89) person-years. During this period, 971 subjects died. The death density was 1 702.03/100 000 person-years. After adjusting for confounders, low-weight patients had a 104% increased risk for all-cause death compared with normal-weight patients (HR=2.04, 95%CI:1.42-2.92). The risk for all-cause death decreased by 34% (HR=0.66, 95%CI: 0.53-0.82), 22% (HR=0.78,95%CI: 0.66-0.92), 38% (HR=0.62, 95%CI: 0.49-0.78) in the patients with simple body obesity, complex overweight and complex obesity, respectively, there was no significant difference for all-cause death in the patients with simple abdominal obesity alone. In subgroup analysis, the risk of all-cause mortality increased in low-weight T2DM patients of different sexes and ages, the mortality risk in women with complex obesity was 50% lower than that in the women with normal body weight, but there was no significant difference in men in the comparison between complex obesity group and normal body weight group. The risk for all-cause mortality was significantly lower in ≥65 years old patients with simple body obesity, complex overweight and complex obesity than in patients with normal body weight (HR=0.61, 95%CI: 0.48-0.78; HR=0.76, 95%CI: 0.63-0.91; HR=0.56,95%CI: 0.42-0.73), there was no significant difference in the patients aged <65 years. There was no significant change in sensitivity analysis. Conclusions: There was an "obesity paradox" in the risk for all-cause mortality in T2DM patients. The risk of all-cause mortality in the low-weight patients was significantly higher than that in normal-weight patients, and the risk for death in the patients with simple body obesity or complex overweight and obesity were significantly lower.

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.

[Research on epidemiological characteristics of pneumonia and correlative factors of length of hospitalization in the elderly aged 60 years and older in Ningbo]

Objective: To investigate the epidemiological characteristics of pneumonia and the related factors of the length of hospitalization of pneumonia in the elderly aged 60 years and older in Ningbo in 2019. Methods: Data on hospitalized cases of pneumonia in the elderly aged 60 years and older in Ningbo in 2019 were collected through the regional health information platform, and the population data of Ningbo in 2019 were obtained through the Zhejiang Provincial Bureau of Statistics. A descriptive epidemiological analysis was conducted on hospitalized cases of pneumonia in the elderly population, and factors related to the length of hospitalization were explored. Results: A total of 15 956 hospitalized cases of pneumonia aged 60 years and older were reported in Ningbo in 2019, and the incidence of pneumonia requiring hospitalization was 1.02% (15 956/1 571 431). The incidence was 1.13% (8 613/760 357) in males and 0.83% (6 759/811 074) in females, and the ratio of male to female cases was 1.27∶1. The highest incidence was found in the ≥80 age group (2.52%), and the lowest incidence was found in the 60-69 age group (0.58%). March, February, and January were the peak period of pneumonia hospitalization. The main types of pneumonia diagnosed were not specified (65.12%), followed by bacterial pneumonia (34.60%). The M(Q1, Q3) of hospitalized patients with pneumonia was 9 (7, 13) days. The results of multivariate logistic regression analysis showed that gender (female: OR=0.911, 95%CI: 0.849-0.978) and older age (70-79 years old: OR=1.211, 95%CI: 1.111-1.321; ≥80 years old group: OR=1.486, 95%CI: 1.365-1.617), settlement method (self-payment: OR=0.567, 95%CI: 0.464-0.691), higher level of hospitals (Grade Ⅱ: OR=1.902,95%CI:1.723-2.100; Grade Ⅲ: OR=1.546,95%CI:1.407-1.698) were associated with the length of hospitalization for pneumonia in people aged 60 years and older in Ningbo. Conclusions: Hospitalization with pneumonia in people aged 60 years and older was high in winter and spring, men and older adults were in high-risk groups in Ningbo in 2019. Gender, age, billing method, and level of hospitals may be related factors to the length of hospitalization for pneumonia.

Dual Role of IGF2BP2 in Osteoimmunomodulation during Periodontitis

Periodontitis is a complex disease characterized by distinct inflammatory stages, with a peak of inflammation in the early phase and less prominent inflammation in the advanced phase. The insulin-like growth factor 2-binding proteins 2 (IGF2BP2) has recently been identified as a new m6A reader that protects m6A-modified messenger RNAs (mRNAs) from decay, thus participating in multiple biological processes. However, its role in periodontitis remains unexplored. Here, we investigated the role of IGF2BP2 in inflammation and osteoclast differentiation using a ligature-induced periodontitis model. Our findings revealed that IGF2BP2 responded to bacterial-induced inflammatory stimuli and exhibited differential expression patterns in early and advanced periodontitis stages, suggesting its dual role in regulating this disease. Depletion of Igf2bp2 contributed to increased release of inflammatory cytokines, thereby exacerbating periodontitis after 3 d of ligature while suppressing osteoclast differentiation and ameliorating periodontitis after 14 d of ligature. Mechanistically, we demonstrated that IGF2BP2 directly interacted with Cd5l and Cd36 mRNA via RNA immunoprecipitation assay. Overexpression of CD36 or recombinant CD5L rescued the osteoclast differentiation ability of Igf2bp2-null cells upon lipopolysaccharide stimulus, and thus the downregulation of Cd36 and Cd5l effectively reversed periodontitis in the advanced stage. Altogether, this study deepens our understanding of the potential mechanistic link among the dysregulated m6A reader IGF2BP2, immunomodulation, and osteoclastogenesis during different stages of periodontitis.

Effects of different dietary vitamin D combinations during the grower phase and the feed restriction phase on growth performance and sternal morphology, mineralization, and related genes expression of bone metabolism in Pekin ducks

Our study aimed to investigate the effects of different dietary vitamin D (VD) combinations during the grower (1-32 d of age) and feed restriction (33-52 d of age) phases on growth performance. We also evaluated sternal morphology, mineralization, and related genes expression of bone metabolism as well as absorption of calcium and phosphorous in duodenal mucosa and kidney in Pekin ducks. During the grower phase, we used 2 VD regimes (Group A: 3,160 IU/kg VD3; Group B: 400 IU/kg VD3 + 69 μg/kg 25-OH-D3). Each dietary treatment had 50 replicate pens of 10 ducks per pen. During the feed restriction phase, 30 replicate pens selected from Group A and Group B, repetitively, were redivided into 5 different dietary VD regimes to form a 2 × 5 experimental design. Each group consisted of 6 replicates, each with 10 ducks. During the feed restriction phase, we evaluated 5 different dietary VD combinations were as follows: T1: 2,000 IU/kg VD3 ; T2: 5,000 IU/kg VD3; T3: 3,620 IU/kg VD3 + 34.5 μg/kg 25-OH-D3; T4: 2,240 IU/kg VD3 + 69 μg/kg 25-OH-D3; T5: 1,800 IU/kg VD3 + 80 μg/kg 25-OH-D3). Results showed that Group B combinations with T5 had a better growth performance and breast meat deposition (P < 0.1). Regardless of 5 dietary VD regimes during the feed restriction phase, Group B significantly increased (P < 0.05) 52 d sternal depth and tended to increase (P < 0.1) 52 d sternal defatted weight, ash content, and phosphate (P) content of ducks. A significant interactive effect (P < 0.05) was observed on the mRNA abundance of DMP1 and Sost1 as well as RANKL/OPG in sternum and of VDR in duodenal mucosa of ducks at 52 d of age between dietary VD combinations during 2 phases. These results indicated that dietary VD regimes during the grower phase could affect the effectiveness of dietary VD regimes during the feed restriction phases; Dietary VD combinations of both phases could affect the genes expression of bone formation and the absorption as well as reabsorption of calcium and phosphorus in duodenum and kidney.

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.

[SRF-rearranged cellular perivascular myoid tumor: a clinicopathological analysis of two cases]

Objective: To investigate the clinicopathological features, immunophenotype, diagnosis and differential diagnosis of SRF-rearranged cellular perivascular myoid tumor. Methods: Two cases of SRF-rearranged cellular perivascular myoid tumor diagnosed in the Department of Pathology, Fudan University Shanghai Cancer Center from October 2021 to March 2022 were collected. Immunohistochemical staining, fluorescence in-situ hybridization (FISH) and next-generation sequencing (NGS) were performed, and the literature was reviewed. Results: Case 1, a 3-month-old boy presented with a painless tumor of the scalp, measuring about 2 cm in diameter. Case 2, a 3-year-old girl complained with a painless tumor of the knee, measuring approximately 1.5 cm in diameter. Microscopically, the tumor had a clear boundary and showed multinodular growth. The tumor was mainly composed of spindle cells arranged in long intersecting fascicles associated with thin, slit-like or branching ectatic vessels, focally forming hemangiopericytoma-like appearance. The tumor cells were abundant, but there was no obvious atypia. Mitotic figures (3-4/10 HPF) were noted. H-caldesmon and SMA were positive in both cases. Case 1 showed diffuse and strong positivity for Desmin, and focally for CKpan. Ki-67 proliferation index was 20% and 30%, respectively. FISH displayed NCOA2 gene translocation in case 1 and the RELA gene translocation in case 2. NGS detected the SRF-NCOA2 gene fusion in case 1 and the SRF-RELA gene fusion in case 2. Both patients underwent local excisions. During the follow-up of 5-14 months, case 1 had no local recurrence, while case 2 developed local recurrence 1 year post operatively. Conclusions: SRF-rearranged cellular perivascular myoid tumor is a novel variant of perivascular cell tumor, which tends to occur in children and adolescents. The tumor forms a broad morphologic spectrum ranging from a pericytic pattern to a myoid pattern, and include hybrid tumors with a mixture of pericytic and myoid patterns. Due to its diffuse hypercellularity and increased mitotic figures and smooth muscle-like immunophenotype, the tumor is easy to be misdiagnosed as myogenic sarcomas. The tumor usually pursues a benign clinical course and rare cases may locally recur.

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.

[Spatial autocorrelation and related factors of stroke mortality in Zhejiang Province based on spatial panel model in 2015-2020]

Objective: To explore the spatial autocorrelation and macro influencing factors of stroke mortality in Zhejiang Province in 2015-2020 and provide a scientific basis for stroke prevention and control strategy. Methods: The data on stroke death were obtained from Zhejiang Chronic Disease Surveillance System. The spatial distribution of stroke mortality was explored by mapping and spatial autocorrelation analysis. The spatial panel model analyzed the correlation between stroke mortality and socioeconomic and healthcare factors. Results: From 2015 to 2020, the average stroke mortality was 68.38/100 thousand. The standard mortality of stroke was high in the areas of east and low in the west, high in the south and low in the north. Moreover, positive spatial autocorrelation was observed (Moran's I=0.274-0.390, P<0.001). Standard mortality of stroke was negatively associated with per capita gross domestic product (GDP) (β=-0.370, P<0.001), per capita health expenditure (β=-0.116, P=0.021), number of beds per thousand population (β=-0.161, P=0.030). Standard mortality of ischemic stroke was negatively associated with per capita GDP (β=-0.310, P=0.002) and standard management rate of hypertension (β=-0.462, P=0.011). Standard mortality of hemorrhagic stroke was negatively associated with per capita GDP (β=-0.481, P<0.001), per capita health expenditure (β=-0.184, P=0.001), number of beds per thousand population (β=-0.288, P=0.001) and standard management rate of hypertension (β=-0.336, P=0.029). Conclusions: A positive spatial correlation existed between stroke mortality in Zhejiang Province in 2015-2020. We must focus more on preventing and controlling strokes in relatively backward economic areas. Moreover, to reduce the mortality of stroke, increasing the investment of government medical and health funds, optimizing the allocation of medical resources, and improving the standard management rate of hypertension are important measures.

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 a τ^{+}τ^{-} Resonance in e^{+}e^{-}→μ^{+}μ^{-}τ^{+}τ^{-} Events with the Belle II Experiment

We report the first search for a nonstandard-model resonance decaying into τ pairs in e^{+}e^{-}→μ^{+}μ^{-}τ^{+}τ^{-} events in the 3.6-10  GeV/c^{2} mass range. We use a 62.8  fb^{-1} sample of e^{+}e^{-} collisions collected at a center-of-mass energy of 10.58 GeV by the Belle II experiment at the SuperKEKB collider. The analysis probes three different models predicting a spin-1 particle coupling only to the heavier lepton families, a Higgs-like spin-0 particle that couples preferentially to charged leptons (leptophilic scalar), and an axionlike particle, respectively. We observe no evidence for a signal and set exclusion limits at 90% confidence level on the product of cross section and branching fraction into τ pairs, ranging from 0.7 to 24 fb, and on the couplings of these processes. We obtain world-leading constraints on the couplings for the leptophilic scalar model for masses above 6.5  GeV/c^{2} and for the axionlike particle model over the entire mass range.

Test of Light-Lepton Universality in the Rates of Inclusive Semileptonic B-Meson Decays at Belle II

We present the first measurement of the ratio of branching fractions of inclusive semileptonic B-meson decays, R(X_{e/μ})=B(B→Xeν)/B(B→Xμν), a precision test of electron-muon universality, using data corresponding to 189  fb^{-1} from electron-positron collisions collected with the Belle II detector. In events where the partner B meson is fully reconstructed, we use fits to the lepton momentum spectra above 1.3  GeV/c to obtain R(X_{e/μ})=1.007±0.009(stat)±0.019(syst), which is the most precise lepton-universality test of its kind and agrees with the standard-model expectation.

Differentially Expressed Circulating Long-Noncoding RNAS in Premature Infants with Respiratory Distress Syndrome

Purpose

Recent studies have addressed the association between lung development and long-noncoding RNAs (lncRNAs). But few studies have investigated the role of lncRNAs in neonatal respiratory distress syndrome (RDS). Thus, this study aimed to compare the expression profile of circulating lncRNAs between RDS infants and controls.

Methods

10 RDS infants and 5 controls were enrolled. RDS patients were further divided into mild and severe RDS subgroups. Blood samples were collected for the lncRNA expression profile. Subsequently, differentially expressed lncRNAs were screened out. Bioinformatics analysis was applied to establish a co-expression network of differential lncRNAs and mRNAs, and predict the underlying biological functions.

Results

A total of 135 differentially expressed lncRNAs were identified, including 108 upregulated and 27 downregulated lncRNAs (fold-change>2 and P<0.05) among the three groups (non-RDS, mild RDS and severe RDS groups). Of these lncRNAs, four were selected as showing higher fold changes and validated by qRT-PCR. ENST00000470527.1, ENST00000504497.1, ENST00000417781.5, and ENST00000440408.5 were increased not only in the plasma of total RDS patients but also in the severe RDS subgroup. Gene Ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) analyses showed that differentially expressed lncRNAs may play important roles in RDS through regulating PI3KAkt, RAS, MAPK, and TGF-β signaling pathways.

Conclusion

The present results found that ENST00000470527.1, ENST00000504497.1, ENST00000417781.5, and ENST00000440408.5 may be invol ved in RDS. This could provide new insight into research of the potential pathophysiological mechanisms of preterm RDS.

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.

[Efficacy of intravenous thrombolysis with tenecteplase in treating the branch atheromatous disease]

Objective: To explore the efficacy of intravenous thrombolysis with tenecteplase (TNK) in the treatment of branch atheromatous disease (BAD). Methods: A total of 148 BAD patients hospitalized in the stroke center of Zhengzhou People's Hospital from January 2020 to March 2023 were retrospectively included. According to whether TNK was used for treatment, the patients were divided into the TNK group (52 cases) and the control group (96 cases). The propensity score matching (PSM) method was used to eliminate baseline differences between the two groups, and 46 pairs were successfully matched. Early neurological deterioration (END) was defined as an increase in the national Institutes of Health Stroke Scale (NIHSS) scores within 7 days of stroke≥2. The 90-day modified Rankin Scale (mRS) was used to compare the long-term efficacy between the two groups. A binary logistic regression model was used to analyze the influencing factors of clinical outcomes in patients with BAD. Results: Among the 92 patients, 62 were males and 30 were females, with an average age of (61.0±9.5) years. After PSM, there were statistically significant differences in NIHSS score at discharge [2 (0, 4) vs 4 (3, 8)] and length of hospital stay [9 (6, 13) d vs 11 (9, 14) d] (both P<0.05) between the two groups. The proportion of mRS 0-2 in TNK group was higher than that in the control group [82.6%(38/46) vs 60.8%(28/46)], while the proportion of END and mRS≥4 was lower than that in the control group [10.8%(5/46) vs 30.4%(14/46); 8.7%(4/46) vs 26.0%(12/46)], with statistically significant differences (P<0.05). The 90-day mortality in the control group was 2.2% (1/46), while no death was detected in the TNK group. Conclusion: Intravenous thrombolysis therapy with TNK can not only increase the proportion of 90-day mRS 0-2 in BAD patients, but also reduce the incidence of END.

Search for an Invisible Z^{'} in a Final State with Two Muons and Missing Energy at Belle II

The L_{μ}-L_{τ} extension of the standard model predicts the existence of a lepton-flavor-universality-violating Z^{'} boson that couples only to the heavier lepton families. We search for such a Z^{'} through its invisible decay in the process e^{+}e^{-}→μ^{+}μ^{-}Z^{'}. We use a sample of electron-positron collisions at a center-of-mass energy of 10.58 GeV collected by the Belle II experiment in 2019-2020, corresponding to an integrated luminosity of 79.7  fb^{-1}. We find no excess over the expected standard-model background. We set 90%-confidence-level upper limits on the cross section for this process as well as on the coupling of the model, which ranges from 3×10^{-3} at low Z^{'} masses to 1 at Z^{'} masses of 8  GeV/c^{2}.

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.

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.

[Progress in evaluating the risk of lymph node metastasis in early colorectal cancer]

Early colorectal cancers refer to invasive cancers that have infiltrated into the submucosa without invading muscularis propria, and approximately 10% of these patients have lymph node metastases that cannot be detected by conventional imaging. According to the guidelines of Chinese Society of Clinical Oncology (CSCO) Colorectal Cancer, early colorectal cancer cases with risk factors for lymph node metastasis (poor tumor differentiation, lymphovascular invasion, deep submucosal invasion and high-grade tumor budding) should receive salvage radical surgical resection; however, the specificity of this risk-stratification is inadequate, making most patients undergo unnecessary surgery. Firstly, this review focuses on the definition, oncological impact importance and controversy of the above "risk factors". Then, we introduce the progress of the risk stratification system for lymph node metastasis in early colorectal cancer, including the identification of new pathological risk factors, the construction of new risk quantitative models based on pathological risk factors, artificial intelligence and machine learning technology and the discovery of novel molecular markers associated with lymph node metastasis based on gene test or liquid biopsy. Aim to enhance clinicians' understanding of the risk assessment of lymph node metastasis in early colorectal cancer; we suggest to take the patient's personal situation, tumor location, anti-cancer intention and other factors into account to make individualized treatment strategies.

[Research progress on prevention and local intervention of oral mucositis in patients with hematopoietic stem cell transplantation]

Oral mucositis (OM) is a common complication during hematopoietic stem cell transplantation. When OM occurs, with the destruction of oral mucosal barrier function, the formation of oral bacterial environment is accelerated, which has a negative impact on the life quality and clinical outcomes of patients. OM can be prevented by keeping the oral cavity clean, using the mouthwash properly, and limiting the delivery of cytotoxic drugs to oral tissues. This review describes the research progress on the prevention and local intervention of OM in patients with hematopoietic stem cell transplantation, in order to provide ideas for the selection of clinical intervention and management strategies on OM, and to provide references for exploring effective management methods for OM.

Search for Lepton-Flavor-Violating τ Decays to a Lepton and an Invisible Boson at Belle II

We search for lepton-flavor-violating τ^{-}→e^{-}α and τ^{-}→μ^{-}α decays, where α is an invisible spin-0 boson. The search uses electron-positron collisions at 10.58 GeV center-of-mass energy with an integrated luminosity of 62.8  fb^{-1}, produced by the SuperKEKB collider and collected with the Belle II detector. We search for an excess in the lepton-energy spectrum of the known τ^{-}→e^{-}ν[over ¯]_{e}ν_{τ} and τ^{-}→μ^{-}ν[over ¯]_{μ}ν_{τ} decays. We report 95% confidence-level upper limits on the branching-fraction ratio B(τ^{-}→e^{-}α)/B(τ^{-}→e^{-}ν[over ¯]_{e}ν_{τ}) in the range (1.1-9.7)×10^{-3} and on B(τ^{-}→μ^{-}α)/B(τ^{-}→μ^{-}ν[over ¯]_{μ}ν_{τ}) in the range (0.7-12.2)×10^{-3} for α masses between 0 and 1.6  GeV/c^{2}. These results provide the most stringent bounds on invisible boson production from τ decays.

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.

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.

Resonances and antiresonances in heat generation by spin current in a quantum dot

We study the heat generation in a quantum dot exposed to a rotating magnetic field and coupled to a normal lead. Both electron-phonon interaction and electron-electron interaction are considered in the dot. We show the emergence of resonances and antiresonances in the heat generation, which we attribute to constructive interference and destructive interference between phonon waves emitted from opposite spin channels in the dot.

Observation of e^{+}e^{-}→ωχ_{bJ}(1P) and Search for X_{b}→ωϒ(1S) at sqrt[s] near 10.75 GeV

We study the processes e^{+}e^{-}→ωχ_{bJ}(1P) (J=0, 1, or 2) using samples at center-of-mass energies sqrt[s]=10.701, 10.745, and 10.805 GeV, corresponding to 1.6, 9.8, and 4.7  fb^{-1} of integrated luminosity, respectively. These data were collected with the Belle II detector during special operations of the SuperKEKB collider above the ϒ(4S) resonance. We report the first observation of ωχ_{bJ}(1P) signals at sqrt[s]=10.745  GeV. By combining Belle II data with Belle results at sqrt[s]=10.867  GeV, we find energy dependencies of the Born cross sections for e^{+}e^{-}→ωχ_{b1,b2}(1P) to be consistent with the shape of the ϒ(10753) state. These data indicate that the internal structures of the ϒ(10753) and ϒ(10860) states may differ. Including data at sqrt[s]=10.653  GeV, we also search for the bottomonium equivalent of the X(3872) state decaying into ωϒ(1S). No significant signal is observed for masses between 10.45 and 10.65  GeV/c^{2}.

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.

[The efficacy and side effects of rigosertib combined with chemotherapy in KRAS mutant colorectal cancer mice]

Objective: To investigate the effect of rigosertib (RGS) combined with classic chemotherapy drugs including 5-fluorouracil, oxaliplatin, and irinotecan in colorectal cancer. Methods: Explore the synergy effects of RGS and 5-fluorouracil (5-FU), oxaliplatin (OXA), and irinotecan (IRI) on colorectal cancer by subcutaneously transplanted tumor models of mice. The mice were randomly divided into control group, RGS group, 5-FU group, OXA group, IRI group, 5-FU+ RGS group, OXA+ RGS group and IRI+ RGS group. The synergy effects of RGS and OXA on KRAS mutant colorectal cancer cell lines in vitro was detected by CCK-8. Ki-67 immunohistochemistry and TdT-mediated dUTP nick-end labeling (TUNEL) staining were performed on the mouse tumor tissue sections, and the extracted tumor tissue was analyzed by western blot. The blood samples of mice after chemotherapy and RGS treatment were collected, blood routine and liver and kidney function analysis were conducted, and H&E staining on liver sections was performed to observe the side effects of chemotherapy and RGS. Results: The subcutaneously transplanted tumor models were established successfully in all groups. 55 days after administration, the fold change of tumor size of OXA+ RGS group was 37.019±8.634, which is significantly smaller than 77.571±15.387 of RGS group (P=0.029) and 92.500±13.279 of OXA group (P=0.008). Immunohistochemical staining showed that the Ki-67 index of tumor tissue in control group, OXA group, RGS group and OXA+ RGS group were (100.0±16.8)%, (35.6±11.3)%, (54.5±18.1)% and (15.4±3.9)%, respectively. The Ki-67 index of OXA+ RGS group was significantly lower than that in control group (P=0.014), but there was no significant difference compared to OXA group and RGS group (OXA: P=0.549; RGS: P=0.218). TUNEL fluorescence staining showed that the apoptotic level of OXA+ RGS group was 3.878±0.547, which was significantly higher than 1.515±0.442 of OXA group (P=0.005) and 1.966±0.261 of RGS group (P=0.008). Western blot showed that the expressions of apoptosis related proteins such as cleaved-PARP, cleaved-caspase 3 and cleaved-caspase 8 in the tumor tissues of mice in the OXA+ RGS group were higher than those in control group, OXA group and RGS group. After the mice received RGS combined with chemotherapy drugs, there was no significant effect on liver and kidney function indexes, but the combined use of oxaliplatin and RGS significantly reduced the white blood cells [(0.385±0.215)×10(9)/L vs (5.598±0.605)×10(9)/L, P<0.001] and hemoglobin[(56.000±24.000)g/L vs (153.333±2.231)g/L, P=0.001] of the mice. RGS, chemotherapy combined with RGS and chemotherapy alone did not significantly increase the damage to liver cells. Conclusions: The combination of RGS and oxaliplatin has a stronger anti-tumor effect on KRAS mutant colorectal cancer. RGS single agent will not cause significant bone marrow suppression and hepatorenal injury in mice, but its side effects may increase correspondingly after combined with chemotherapy.

Search for a Dark Photon and an Invisible Dark Higgs Boson in μ^{+}μ^{-} and Missing Energy Final States with the Belle II Experiment

The dark photon A^{'} and the dark Higgs boson h^{'} are hypothetical particles predicted in many dark sector models. We search for the simultaneous production of A^{'} and h^{'} in the dark Higgsstrahlung process e^{+}e^{-}→A^{'}h^{'} with A^{'}→μ^{+}μ^{-} and h^{'} invisible in electron-positron collisions at a center-of-mass energy of 10.58 GeV in data collected by the Belle II experiment in 2019. With an integrated luminosity of 8.34  fb^{-1}, we observe no evidence for signal. We obtain exclusion limits at 90% Bayesian credibility in the range of 1.7-5.0 fb on the cross section and in the range of 1.7×10^{-8}-200×10^{-8} on the effective coupling ϵ^{2}×α_{D} for the A^{'} mass in the range of 4.0  GeV/c^{2}<M_{A^{'}}<9.7  GeV/c^{2} and for the h^{'} mass M_{h^{'}}<M_{A^{'}}, where ϵ is the mixing strength between the standard model and the dark photon and α_{D} is the coupling of the dark photon to the dark Higgs boson. Our limits are the first in this mass range.

[EWSR1-SMAD3 positive fibroblastic tumor: a clinicopathological analysis]

Objective: To investigate the clinicopathological features, immunophenotypes and molecular genetics of EWSR1-SMAD3 positive fibroblastic tumor (ESFT) with an emphasis on differential diagnosis. Methods: The clinicopathological data, immunohistochemical profiles and molecular profiles of 3 ESFT cases diagnosed at the Department of Pathology, Fudan University Shanghai Cancer Center from 2018 to 2021were analyzed. The related literature was also reviewed. Results: There were two males and one female. The patients were 24, 12 and 36 years old, respectively. All three tumors occurred in the subcutis of the foot with the disease duration of 6 months to 2 years. The tumors were presented with a slowly growing mass or nodule, accompanied with pain in 1 patient. The tumors ranged in size from 0.1 to 1.6 cm (mean, 1.0 cm). Microscopically, the tumors were located in the subcutaneous tissue with a nodular or plexiform growth pattern. They were composed of cellular fascicles of bland spindle cells with elongated nuclei and fine chromatin. One of the tumors infiltrated into adjacent adipose tissue. There was no nuclear atypia or mitotic activities. All three tumors showed prominent stromal hyalinization with zonal pattern present in one case. Focal punctate calcification was noted in two cases. The immunohistochemical studies showed that tumor cells were diffusely positive for ERG and negative for CD31 and CD34, with Ki-67 index less than 2%. Fluorescence in situ hybridization on the two tested cases identified EWSR1 gene rearrangement. The next generation sequencing analysis demonstrated EWSR1-SMAD3 fusion in all three cases. During the follow up, one patient developed local recurrence 24 months after the surgery. Conclusions: ESFT is a benign fibroblastic neoplasm and has a predilection for the foot, characterized by ERG immunoreactivity and EWSR1-SMAD3 fusion. Local recurrence might occur when incompletely excised. Familiarity with its clinicopathological features is helpful in distinguishing it from other spindle cell neoplasms that tend to occur at acral sites.

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}}}.

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}.

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})%.

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.