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Using data samples collected with the BESIII detector operating at the BEPCII storage ring, the cross section of the inclusive process e^{+}e^{-}âη+X, normalized by the total cross section of e^{+}e^{-}âhadrons, is measured at eight center-of-mass energy points from 2.0000 to 3.6710 GeV. These are the first measurements with momentum dependence in this energy region. Our measurement shows a significant discrepancy compared to the existing fragmentation functions. To address this discrepancy, a new QCD analysis is performed at the next-to-next-to-leading order with hadron mass corrections and higher twist effects, which can explain both the established high-energy data and our measurements reasonably well.
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Using (10.087±0.044)×10^{9} J/ψ events collected with the BESIII detector at the BEPCII storage ring, the processes ΛpâΛp and Λ[over ¯]pâΛ[over ¯]p are studied, where the Λ/Λ[over ¯] baryons are produced in the process J/ψâΛΛ[over ¯] and the protons are the hydrogen nuclei in the cooling oil of the beam pipe. Clear signals are observed for the two reactions. The cross sections in -0.9≤cosθ_{Λ/Λ[over ¯]}≤0.9 are measured to be σ(ΛpâΛp)=(12.2±1.6_{stat}±1.1_{syst}) and σ(Λ[over ¯]pâΛ[over ¯]p)=(17.5±2.1_{stat}±1.6_{syst}) mb at the Λ/Λ[over ¯] momentum of 1.074 GeV/c within a range of ±0.017 GeV/c, where the θ_{Λ/Λ[over ¯]} are the scattering angles of the Λ/Λ[over ¯] in the Λp/Λ[over ¯]p rest frames. Furthermore, the differential cross sections of the two reactions are also measured, where there is a slight tendency of forward scattering for ΛpâΛp, and a strong forward peak for Λ[over ¯]pâΛ[over ¯]p. We present an approach to extract the total elastic cross sections by extrapolation. The study of Λ[over ¯]pâΛ[over ¯]p represents the first study of antihyperon-nucleon scattering, and these new measurements will serve as important inputs for the theoretical understanding of the (anti)hyperon-nucleon interaction.
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Objective: To explore the differences in metabolites and metabolic pathways in the aqueous humor between patients with presenile cataracts and senile cataracts. Methods: This metabolomic study was conducted at Tianjin Medical University Eye Hospital from August 2020 to September 2022. Eight patients with presenile cataracts (8 eyes) and 8 patients with senile cataracts (9 eyes) were included. Data were collected, including age, gender, preoperative uncorrected visual acuity, intraocular pressure, lens dysfunction index, and axial length. Aqueous humor and anterior capsule tissue samples were obtained during cataract surgery. Metabolites in the aqueous humor were detected using Liquid Chromatography-Mass Spectrometry in a non-targeted approach. The principal component analysis, differential analysis, clustering analysis, and correlation analysis were performed to identify differentially expressed metabolites. These metabolites were ranked based on the fold change (FC). The receiver operating characteristic (ROC) curve analysis and metabolic enrichment analysis were used to identify differential pathways and potential biomarkers for presenile cataracts. Immunohistochemistry was conducted on anterior capsule tissues, and pyruvate levels were measured by colorimetry to validate metabolomic results. Results: Patients with presenile cataracts included 7 males and 1 female, with a mean age of (37.50±4.90) years. Patients with senile cataracts were 7 males and 1 female, with a mean age of (73.44±5.22) years. Except for age, there were no significant differences in baseline data (P>0.05). A total of 347 differential metabolites were identified, 10 of which were potential biomarkers for presenile cataract according to the ROC curve analysis (all P<0.05), including propoxycaine (log2FC=7.26), 2-methyl-2, 3, 4, 5-tetrahydro-1, 5-benzodiazepine-4-ketone (log2FC=6.35), l-pyroglutamic acid (log2FC=-1.72), leanly-proline (log2FC=-0.77), and choline (log2FC=-0.56) in the positive ion mode, and N-phenylacetyl glutamine (log2FC=-1.84), pyruvate (log2FC=1.07), ascorbic acid (log2FC=0.92), pseudouracil nucleoside (log2FC=-0.68), and palmitic acid (log2FC=-0.51) in the negative ion mode. The metabolic enrichment analysis identified 72 differential pathways (32 cationic and 40 anionic), with significant differences in glutathione metabolism, cysteine and methionine metabolism, glycolysis or gluconeogenesis, pyruvate metabolism, and the citric acid cycle (P<0.05). The experimental validation showed reduced lactate dehydrogenase and increased pyruvate levels in patients with presenile cataracts (P<0.05). Conclusions: Pyruvate and nine other metabolites may serve as potential biomarkers for presenile cataracts. Pathways involving glutathione metabolism, cysteine and methionine metabolism, glycolysis or gluconeogenesis, pyruvate metabolism, and the citric acid cycle are notably dysregulated in patients with presenile cataracts.
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Humor Acuoso , Catarata , Metabolómica , Humanos , Catarata/metabolismo , Humor Acuoso/metabolismo , Metabolómica/métodos , Biomarcadores/metabolismo , Masculino , FemeninoRESUMEN
We report the measurement of the inclusive cross sections for e^{+}e^{-}ânOCH (where nOCH denotes non-open charm hadrons) with improved precision at center-of-mass (c.m.) energies from 3.645 to 3.871 GeV. We observe three resonances: R(3760), R(3780), and R(3810) with significances of 8.1σ, 13.7σ, and 8.8σ, respectively. The R(3810) state is observed for the first time, while the R(3760) and R(3780) states are observed for the first time in the nOCH cross sections. Two sets of resonance parameters describe the energy-dependent line shape of the cross sections well. In set I [set II], the R(3810) state has mass (3805.7±1.1±2.7) [(3805.7±1.1±2.7)] MeV/c^{2}, total width (11.6±2.9±1.9) [(11.5±2.8±1.9)] MeV, and an electronic width multiplied by the nOCH decay branching fraction of (10.9±3.8±2.5) [(11.0±3.4±2.5)] eV. In addition, we measure the branching fractions B[R(3760)ânOCH]=(25.2±16.1±30.4)%[(6.4±4.8±7.7)%] and B[R(3780)ânOCH]=(12.3±6.6±8.3)%[(10.4±4.8±7.0)%] for the first time. The R(3760) state can be interpreted as an open-charm (OC) molecular state, but containing a simple four-quark state component. The R(3810) state can be interpreted as a hadrocharmonium state.
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Based on (10087±44)×10^{6} J/ψ events collected with the BESIII detector, a partial wave analysis of the decay J/ψâγK_{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/ψâγX(2370)]×B[X(2370)âf_{0}(980)η^{'}]×B[f_{0}(980)âK_{S}^{0}K_{S}^{0}]=(1.31±0.22(stat)_{-0.84}^{+2.85}(syst))×10^{-5}. The statistical significance of the X(2370) is greater than 11.7σ and the spin parity is determined to be 0^{-+} for the first time. The measured mass and spin parity of the X(2370) are consistent with the predictions of the lightest pseudoscalar glueball.
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We present measurements of the Born cross sections for the processes e^{+}e^{-}âωχ_{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^{-}âωχ_{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^{-}âωχ_{c1} line shape and determine the mass and width to be M=(4544.2±18.7±1.7) MeV/c^{2} and Γ=(116.1±33.5±1.7) MeV, respectively. The structure of this line shape, observed for the first time, requires further understanding.
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We perform a study of the χ_{c1}(3872) line shape using the data samples of e^{+}e^{-}âγχ_{c1}(3872), χ_{c1}(3872)âD^{0}D[over ¯]^{0}π^{0}, and π^{+}π^{-}J/ψ collected with the BESIII detector. The effects of the coupled channels and the off-shell D^{*0} are included in the parametrization of the line shape. The line shape mass parameter is obtained to be M_{X}=(3871.63±0.13_{-0.05}^{+0.06}) MeV. Two poles are found on the first and second Riemann sheets corresponding to the D^{*0}D[over ¯]^{0} branch cut. The pole location on the first sheet is much closer to the D^{*0}D[over ¯]^{0} threshold than the other, and is determined to be 7.04±0.15_{-0.08}^{+0.07} MeV above the D^{0}D[over ¯]^{0}π^{0} threshold with an imaginary part -0.19±0.08_{-0.19}^{+0.14} MeV.
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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/ψâγ3(π^{+}π^{-}) decay is performed. A significant distortion at 1.84 GeV/c^{2} in the line shape of the 3(π^{+}π^{-}) invariant mass spectrum is observed for the first time, which could be resolved by two overlapping resonant structures, X(1840) and X(1880). The new state X(1880) is observed with a statistical significance larger than 10σ. The mass and width of X(1880) are determined to be 1882.1±1.7±0.7 MeV/c^{2} and 30.7±5.5±2.4 MeV, respectively, which indicates the existence of a pp[over ¯] bound state.
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We present cross sections for the reaction e^{+}e^{-}âK_{S}^{0}K_{L}^{0} at center-of-mass energies ranging from 3.51 to 4.95 GeV using data samples collected in the BESIII experiment, corresponding to a total integrated luminosity of 26.5 fb^{-1}. The ratio of neutral-to-charged kaon form factors at large momentum transfers (12
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We perform for the first time an amplitude analysis of the decay D^{+}âK_{S}^{0}π^{+}η and report the observation of the decay D^{+}âK_{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^{+}âK_{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^{+}âK_{S}^{0}π^{+}η is measured to be (1.27±0.04_{stat}±0.03_{syst})%. The branching fractions of intermediate processes D^{+}âK_{S}^{0}a_{0}(980)^{+} with a_{0}(980)^{+}âπ^{+}η and D^{+}âπ^{+}K[over ¯]_{0}^{*}(1430)^{0} with K[over ¯]_{0}^{*}(1430)^{0}âK_{S}^{0}η are measured to be (1.33±0.05_{stat}±0.04_{syst})% and (0.14±0.03_{stat}±0.01_{syst})%, respectively.
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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}^{+}âπ^{+}π^{-}e^{+}ν_{e}, where the D_{s}^{+} is produced via the process e^{+}e^{-}âD_{s}^{*±}D_{s}^{∓}. We observe the f_{0}(980) in the π^{+}π^{-} system and the branching fraction of the decay D_{s}^{+}âf_{0}(980)e^{+}ν_{e} with f_{0}(980)âπ^{+}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}^{+}âf_{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 câs 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}^{+}âf_{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}^{+}âf_{0}(500)e^{+}ν_{e}, f_{0}(500)âπ^{+}π^{-} decay is set to be 3.3×10^{-4} at 90% confidence level.
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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}^{+}âη^{'}µ^{+}ν_{µ}, with a statistical significance larger than 10σ, and the measurements of the D_{s}^{+}âηµ^{+}ν_{µ} and D_{s}^{+}âη^{'}µ^{+}ν_{µ} decay dynamics for the first time. The branching fractions of D_{s}^{+}âηµ^{+}ν_{µ} and D_{s}^{+}âη^{'}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}^{+}âηe^{+}ν_{e} and D_{s}^{+}âη^{'}e^{+}ν_{e}, the ratios of the decay widths are examined both inclusively and in several â^{+}ν_{â} 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 câs Cabibbo-Kobayashi-Maskawa matrix element |V_{cs}| are determined. The results based on the two-parameter series expansion are f_{+,0}^{η}(0)|V_{cs}|=0.452±0.010_{stat}±0.007_{syst} and f_{+,0}^{η^{'}}(0)|V_{cs}|=0.504±0.037_{stat}±0.012_{syst}, which help to constrain present models on f_{+,0}^{η^{(')}}(0). The forward-backward asymmetries are determined to be ⟨A_{FB}^{η}⟩=-0.059±0.031_{stat}±0.005_{syst} and ⟨A_{FB}^{η^{'}}⟩=-0.064±0.079_{stat}±0.006_{syst} for the first time, which are consistent with the theoretical calculation.
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Based on data samples collected with the BESIII detector at the BEPCII collider, the process e^{+}e^{-}âΣ^{+}Σ[over ¯]^{-} is studied at center-of-mass energies sqrt[s]=2.3960, 2.6454, and 2.9000 GeV. Using a fully differential angular description of the final state particles, both the relative magnitude and phase information of the Σ^{+} electromagnetic form factors in the timelike region are extracted. The relative phase between the electric and magnetic form factors is determined to be sinΔΦ=-0.67±0.29(stat)±0.18(syst) at sqrt[s]=2.3960 GeV, ΔΦ=55°±19°(stat)±14°(syst) at sqrt[s]=2.6454 GeV, and 78°±22°(stat)±9°(syst) at sqrt[s]=2.9000 GeV. For the first time, the phase of the hyperon electromagnetic form factors is explored in a wide range of four-momentum transfer. The evolution of the phase along with four-momentum transfer is an important input for understanding its asymptotic behavior and the dynamics of baryons.
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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/ψâΞ^{-}Ξ[over ¯]^{+}âΛ(pπ^{-})π^{-}Λ[over ¯](n[over ¯]π^{0})π^{+} and its charge-conjugate channel. The precisions of α_{Λ0} for Λânπ^{0} and α[over ¯]_{Λ0} for Λ[over ¯]ân[over ¯]π^{0} compared to world averages are improved by factors of 4 and 1.7, respectively. The ratio of decay asymmetry parameters of Λânπ^{0} to that of Λâpπ^{-}, ⟨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^{-}âΛπ^{-} and in Λânπ^{0} with the best precision to date.
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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}^{+}âΞ^{0}K^{+} is studied with a full angular analysis. The corresponding decay asymmetry is measured for the first time to be α_{Ξ^{0}K^{+}}=0.01±0.16(stat)±0.03(syst). This result reflects the noninterference effect between the S- and P-wave amplitudes. The phase shift between S- and P-wave amplitudes has two solutions, which are δ_{p}-δ_{s}=-1.55±0.25(stat)±0.05(syst) rad or 1.59±0.25(stat)±0.05(syst) rad.
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Objective: To quantify the associations between periconceptional maternal homocysteine (HCY) and offspring's birth weight and risk of small for gestational age (SGA) infant. Methods: The 19 984 mother-child pairs in this prospective cohort study were recruited from the Shanghai preconception cohort; the infants were delivered from 1st September 2016 to 11th November 2022. A standardized questionnaire was used to collect the mothers' demographic information, medical history, dietary supplement use, and maternal complications during pregnancy, and their serum samples were collected. Serum HCY, folate, and vitamin B12 were measured using chemiluminescent microparticle immunoassay based on serum sample drawn at enrollment. Birth weight data were obtained from medical records. Multiple imputation methods were applied to handle missing data in key variables. Multivariable linear regression and Poisson regression models were used to analyze the relationship between maternal HCY concentration during the periconceptional period and the birth weight and SGA risk of the offspring. Results: A total of 9 452 pairs were enrolled preconceptionally and the remaining 10 532 pairs were enrolled in early pregnancy. The proportion of mothers whose pregnancy age was greater than 35 years was 9.2% (1 832/19 984), the proportion of primiparous women was 76.5% (15 283/19 984), the proportion of pre-pregnancy overweight and obesity was 14.0% (2 804/19 984), the proportion of using folic acid supplements before pregnancy was 21.4% (4 272/19 984), and the proportion of those who supplemented with folic acid during early pregnancy was 85.2% (8 976/10 532); gestational diabetes mellitus was in 6.2% (1 245/19 984), gestational hypertensive syndrome in 3.6% (711/19 984). The birth weight of the offspring was (3 297±468) g, and there were 1 962 SGA children (9.8%). The HCY concentration in the overall population in appropriate for gestational age during the periconceptional period was (7.9±3.2) µmol/L, with (8.3±3.7) µmol/L in the preconception subgroup and (7.3±2.4) µmol/L in the early pregnancy subgroup. After adjustment for the covariates of perinatal demographic information, adverse pregnancy outcomes, serum folate and vitamin B12, increased maternal periconceptional HCY was significantly associated with lower offspring birth weight (ß=-2.30, 95%CI -4.43--0.16, P=0.035). Only the early pregnancy subgroup was significantly associated with lower offspring birth weight (ß=-7.39, 95%CI-11.50--3.21, P<0.001). No association was found between peripregnancy HCY and offspring SGA risk. However, elevated HCY in early pregnancy was associated with an increased risk of SGA in the offspring (RR=1.05, 95%CI 1.01-1.08, P=0.002). Periconceptional vitamin B12 was a mediator of the association between HCY and offspring birth weight, accounting for 16.5%, 41.2% and 5.4% of its total effect in the overall periconceptional population, the pre-pregnancy subgroup and the early pregnancy subgroup, respectively. Conclusions: Maternal periconceptional HCY level is associated with lower birth weight in offspring, but not with the risk of SGA. Elevated maternal HCY in early pregnancy subgroup may be associated with increased risk of SGA in offspring.
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Ácido Fólico , Vitaminas , Embarazo , Lactante , Humanos , Femenino , Adulto , Peso al Nacer , Estudios Prospectivos , China , HomocisteínaRESUMEN
In this article, we reported a 28-year-old female patient who presented with intermittent hemoptysis, cough, and sputum production. Laboratory tests showed no abnormalities in the blood counts or inflammatory markers, and the sputum cultures were negative. A chest computed tomography scan showed bronchiectasis associated with infection in the middle and lower lobes of the right lung and right pleural thickening. We performed bronchoalveolar lavage by bronchoscopy in the dorsal segment of the right lower lobe and found Mycobacterium avium intracellulare complex (MAC) by Next Generation Sequencing (NGS) of bronchoalveolar lavage fluid (BALF). The patient's symptoms improved significantly after anti-mycobacterium treatment and the extent of infection was reduced on imaging. To further identify the cause of bronchiectasis, the patient is tall and thin, with slender limbs. Cardiac color ultrasound showed the widening of aortic sinus. Her genetic testing of blood samples revealed the gene mutation in the FBN1 gene (c.4349G>A). Based on these results, she was diagnosed with Marfan syndrome.
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Bronquiectasia , Síndrome de Marfan , Infección por Mycobacterium avium-intracellulare , Humanos , Femenino , Adulto , Infección por Mycobacterium avium-intracellulare/diagnóstico , Síndrome de Marfan/complicaciones , Esputo/microbiología , Bronquiectasia/microbiología , Complejo Mycobacterium aviumRESUMEN
Using data samples with an integrated luminosity of 5.85 fb^{-1} collected at center-of-mass energies from 4.61 to 4.95 GeV with the BESIII detector operating at the BEPCII storage ring, we measure the cross section for the process e^{+}e^{-}âK^{+}K^{-}J/ψ. A new resonance with a mass of M=4708_{-15}^{+17}±21 MeV/c^{2} and a width of Γ=126_{-23}^{+27}±30 MeV is observed in the energy-dependent line shape of the e^{+}e^{-}âK^{+}K^{-}J/ψ cross section with a significance over 5σ. The K^{+}J/ψ system is also investigated to search for charged charmoniumlike states, but no significant Z_{cs}^{+} states are observed. Upper limits on the Born cross sections for e^{+}e^{-}âK^{-}Z_{cs}(3985)^{+}/K^{-}Z_{cs}(4000)^{+}+c.c. with Z_{cs}(3985)^{±}/Z_{cs}(4000)^{±}âK^{±}J/ψ are reported at 90% confidence levels. The ratio of branching fractions {[B(Z_{cs}(3985)^{+}âK^{+}J/ψ)]/B[Z_{cs}(3985)^{+}â(D[over ¯]^{0}D_{s}^{*+}+D[over ¯]^{*0}D_{s}^{+})]} is measured to be less than 0.03 at 90% confidence level.
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We study the process e^{+}e^{-}âΛ_{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}^{+}âpK^{-}π^{+}. Flat cross sections around 4.63 GeV are obtained and no indication of the resonant structure Y(4630), as reported by Belle, is found. In addition, no oscillatory behavior is discerned in the |G_{eff}| energy dependence of Λ_{c}^{+}, in contrast to what is seen for the proton and neutron cases. Analyzing the cross section together with the polar-angle distribution of the Λ_{c}^{+} baryon at each energy point, the moduli of electric and magnetic form factors (|G_{E}| and |G_{M}|) are extracted and separated. For the first time, the energy dependence of the form factor ratio |G_{E}/G_{M}| is observed, which can be well described by an oscillatory function.
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The quantum entangled J/ψâΣ^{+}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^{+}ânπ^{+} and Σ[over ¯]^{-}ân[over ¯]π^{-}. The CP-odd weak decay parameters of the decays Σ^{+}ânπ^{+} (α_{+}) and Σ[over ¯]^{-}ân[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^{+}âpπ^{0} and Σ[over ¯]^{-}âp[over ¯]π^{0}, respectively.