[The correlations of abdominal adipose tissue with anthropometric and metabolic parameters in obese children by magnetic resonance imaging]

Objective: To explore abdominal fat mass distribution and contents among obese children via magnetic resonance imaging (MRI), and analyze the correlations of abdominal adipose tissue with anthropometric and metabolic parameters. Methods: Cross-sectional study. There were 60 obese children admitted to the Children's Health Care Department and Endocrinology Department at Children's Hospital of Nanjing Medical University from July 2016 to December 2018. Children's gender, age, height, weight, body composition, waist circumference and blood pressure were recorded. The levels of fasting blood glucose, lipids, insulin were measured, and liver ultrasound was performed, and the body mass index Z score (BMI-Z), waist-to-height ratio (WHtR) and homeostasis model assessment of insulin resistance (HOMA-IR) were calculated. In addition, contents of subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT) and total abdominal adipose tissue (TAAT) were calculated according to feedback of abdominal MRI scan images. The associations between the contents of abdominal adipose tissue, physical examination status and metabolic disorders among obese children were analyzed through correlation analysis and regression analysis. Receiver operating characteristic (ROC) curve was used to compare the accuracy of fat mass in different parts of the abdomen in predicting their metabolic disorders. Results: A total of 60 children were enrolled in the study, included 44 boys and 16 girls, with age of (9.2±1.4) years. The contents of SAT, VAT and TAAT among the 60 children were positively associated with BMI-Z (r=0.60, 0.46, 0.59), body fat percentage (r=0.64, 0.67, 0.68) and waist-to-height ratio (r=0.60, 0.57, 0.61) (all P<0.01). Meanwhile, contents of SAT and TAAT were also positively correlated with systolic blood pressure (r=0.47, 0.49), triglyceride (r=0.33, 0.35) and HOMA-IR (r=0.33, 0.28)(all P<0.05). In order to adjust the confounding effects among various variables, regression analysis was applied and the result showed that the body fat percentage (β=0.59, 0.66, 0.65) and waist-to-height ratio (β=0.53, 0.63, 0.59) were most related to abdominal fat contents (all P<0.01), including SAT, VAT and TAAT among obese children. According to ROC, SAT had outstanding evaluation performances for the diagnosis of insulin resistance and metabolic syndrome, while VAT had excellent evaluation performances for non-alcoholic fatty liver disease (area under curve=0.68, 0.69, 0.69, 95%CI 0.54-0.82, 0.55-0.84, 0.53-0.85, P=0.017, 0.014, 0.019). Conclusions: As one of the best indexes, body fat percentage and WHtR can be used to predict the contents of SAT, VAT and TAAT among obese children. With the increase of abdominal SAT or VAT, the risks for insulin resistance, metabolic syndrome and non-alcoholic fatty liver disease would increase. Assessment of abdominal fat and metabolic risks in obese children should combine BMI-Z with waist circumference and body composition analysis.

Observation of a State X(2600) in the π^{+}π^{-}η' System in the Process J/ψ→γπ^{+}π^{-}η'

Based on (10087±44)×10^{6}  J/ψ events collected with the BESIII detector, the process J/ψ→γπ^{+}π^{-}η^{'} is studied using two largest decay channels of the η^{'} meson, η^{'}→γπ^{+}π^{-} and η^{'}→ηπ^{+}π^{-}, η→γγ. A new resonance, which we denote as the X(2600), is observed with a statistical significance larger than 20σ in the π^{+}π^{-}η^{'} invariant mass spectrum, and it has a connection to a structure around 1.5  GeV/c^{2} in the π^{+}π^{-} invariant mass spectrum. A simultaneous fit on the π^{+}π^{-}η^{'} and π^{+}π^{-} invariant mass spectra with the two η^{'} decay modes indicates that the mass and width of the X(2600) state are 2618.3±2.0_{-1.4}^{+16.3}  MeV/c^{2} and 195±5_{-17}^{+26}  MeV, where the first uncertainties are statistical, and the second systematic.

Observation of J/ψ Electromagnetic Dalitz Decays to X(1835), X(2120), and X(2370)

Using a sample of about 10^{10}  J/ψ events collected at a center-of-mass energy sqrt[s]=3.097  GeV with the BESIII detector, the electromagnetic Dalitz decays J/ψ→e^{+}e^{-}π^{+}π^{-}η^{'}, with η^{'}→γπ^{+}π^{-} and η^{'}→π^{+}π^{-}η, have been studied. The decay J/ψ→e^{+}e^{-}X(1835) is observed with a significance of 15σ, and also an e^{+}e^{-} invariant-mass dependent transition form factor of J/ψ→e^{+}e^{-}X(1835) is presented for the first time. The intermediate states X(2120) and X(2370) are also observed in the π^{+}π^{-}η^{'} invariant-mass spectrum with significances of 5.3σ and 7.3σ. The corresponding product branching fractions for J/ψ→e^{+}e^{-}X, X→π^{+}π^{-}η^{'} [X=X(1835), X(2120), and X(2370)] are reported.

Properties of Daily Helium Fluxes

We present the precision measurement of 2824 daily helium fluxes in cosmic rays from May 20, 2011 to October 29, 2019 in the rigidity interval from 1.71 to 100 GV based on 7.6×10^{8} helium nuclei collected with the Alpha Magnetic Spectrometer (AMS) aboard the International Space Station. The helium flux and the helium to proton flux ratio exhibit variations on multiple timescales. In nearly all the time intervals from 2014 to 2018, we observed recurrent helium flux variations with a period of 27 days. Shorter periods of 9 days and 13.5 days are observed in 2016. The strength of all three periodicities changes with time and rigidity. In the entire time period, we found that below ∼7  GV the helium flux exhibits larger time variations than the proton flux, and above ∼7  GV the helium to proton flux ratio is time independent. Remarkably, below 2.4 GV a hysteresis between the helium to proton flux ratio and the helium flux was observed at greater than the 7σ level. This shows that at low rigidity the modulation of the helium to proton flux ratio is different before and after the solar maximum in 2014.

[Association between the presence of solid or micropapillary components and survival outcome in stage ⅠA lung adenocarcinoma cases: a retrospective cohort study]

Objectives: To examine the influence of the proportion of pathological subtypes on the prognosis of stage ⅠA lung adenocarcinoma cases, and to explore the association between the presence/absence of solid or micropapillary (S/M) components and survival outcome. Methods: Totally 321 patients with stage ⅠA lung adenocarcinoma who received complete surgical resection at Department of Thoracic Surgery, Tongji University Affiliated Shanghai Pulmonary Hospital from January 2011 to December 2013 were retrospectively analyzed. There were 130 males and 191 females, aging 59(11) years (M(IQR)) (range: 55 to 66 years). The diagnostic value of the proportion of each pathological growth subtype on relapse-free survival (RFS) and overall survival (OS) were analyzed by using receiver operator characteristic curve. Patients were firstly divided into two groups according to the presence or absence of S/M components. And patients without S/M components were farther divided into two groups according to predominant growth pattern. There were three groups in total: with S/M components (group S/M⁺), without S/M components and lepidic growth pattern predominant (group S/M^-LPA), without S/M components and papillary or acinar growth pattern predominant (group S/M^-P/A). Kaplan-Meier method were used to draw the survival curves of the three groups, and Log-rank test were used to compare RFS and OS among the three groups. Cox proportional risk model was used to verify whether the presence of S/M components was a prognostic factor on RFS. Results: The proportion of S/M components had no diagnostic value for recurrence (solid: area under curve (AUC)=0.588, P=0.095; micropapillary: AUC=0.566, P=0.106) and death (AUC=0.589, P=0.104; AUC=0.607, P=0.056). The 5-year RFS rate of group S/M^-LPA, S/M^-P/A and S/M⁺ were 92.4%, 82.3% and 77.3%, respectively (all P<0.05), while the 5-year OS rate were 97.4%, 94.5% and 83.2%, respectively (all P<0.05). Multivariable analysis showed that the 3 groups were independent predictors of recurrence (S/M^-P/A vs. S/M^- LPA: HR=2.691, 95%CI: 1.249 to 5.799, P=0.011; S/M⁺ vs. S/M^-LPA, HR=6.763, 95%CI: 3.050 to 14.996, P<0.01). Conclusions: The proportion of S/M components in stage ⅠA lung adenocarcinoma with complete resection cases did not affect survival outcome. New grouping method based on the presence or absence of S/M components were significantly associated with patient survival outcomes: S/M⁺ patients had the worst prognosis and S/M^-LPA patients had the best prognosis.

[Identification of rare variants in exons of NLRC4 gene in patients with type 1 diabetes and their impact on gene function]

Objective: To identify rare variants in exon and exon-intron boundary of containing NLR family CARD domain protein 4 (NLRC4) in type 1 diabetes (T1DM) patients, and to explore their effects on gene function. Methods: A total of 508 T1DM patients and 527 healthy controls in the Department of Metabolic Endocrinology, Second Xiangya Hospital of Central South University from August 2017 to September 2020 were selected. The case group included 264 males and 244 females, and the age [M (Q₁, Q₃)] was [27 (11, 43)] years. The control group included 290 males and 237 females, and their age［M（Q₁，Q₃）］was [47 (36, 60)] years old. Identification of rare variants in exons of NLRC4 gene in T1DM patients and healthy controls was performed and verified by next-generation sequencing and sanger sequencing. The NLRC4 gene wild-type and mutant plasmids were constructed and transfected into 293T cells. Western blot (WB) was used to detect the expression of NLRC4 protein and cleavage products of pro-cysteinyl aspartate specific proteinase(procaspase-1). Cycloheximide (CHX) was added to 293T cells transfected with wild-type or mutant NLRC4 plasmid to detect the degradation of NLRC4 protein. The localization of NLRC4 protein was detected by immunofluorescence, and the concentration of IL-1β in the cell supernatant was detected by enzyme-linked immunosorbent assay (ELISA). Results: The sequencing results showed that 4 patients and 2 healthy controls had a heterozygous variant c.208C>T in exon 3 of the NLRC4 gene. Two patient had a heterozygous variant c.1564T>C in exon 4, and 1 patients had c.1219G>C in exon 4. These three variants might be pathogenic variants in T1DM. In 293T cells transfected with NLRC4 wild-type and c.208C>T、c.1564T>Cc.1219G>C mutant plasmids, the expression level, degradation rate, localization of NLRC4 protein and the content of cleavage products of procaspase-1 did not change significantly. However, the concentration of IL-1β secreted by 293T cells transfected with c.1219G>C and c.208C>T plasmid [M(Q₁, Q₃)] was 15.25 (12.98, 17.52) and 15.44 (13.81, 17.07) ng/L, respectively, which was lower than 18.70 (16.59, 20.81) ng/L of 293T cells transfected wild-type plasmid (P=0.020, 0.010). Conclusions: NLRC4 gene rare variants c.208C>T, c.1564T>C and c.1219G>C may not change the protein expression, degradation and localization, but c.208C>T and c.1219G>C may inhibit the secretion of IL-1β. This result suggests that NLRC4 rare variants may have an impact on gene function.

Observation of the Singly Cabibbo Suppressed Decay Λ_{c}^{+}→nπ^{+}

The singly Cabibbo-suppressed decay Λ_{c}^{+}→nπ^{+} is observed for the first time with a statistical significance of 7.3σ by using 3.9  fb^{-1} of e^{+}e^{-} collision data collected at center-of-mass energies between 4.612 and 4.699 GeV with the BESIII detector at BEPCII. The branching fraction of Λ_{c}^{+}→nπ^{+} is measured to be (6.6±1.2_{stat}±0.4_{syst})×10^{-4}. By taking the upper limit of branching fractions of Λ_{c}^{+}→pπ^{0} from the Belle experiment, the ratio of branching fractions between Λ_{c}^{+}→nπ^{+} and Λ_{c}^{+}→pπ^{0} is calculated to be larger than 7.2 at the 90% confidence level, which disagrees with most predictions of the available phenomenological models. In addition, the branching fractions of the Cabibbo-favored decays Λ_{c}^{+}→Λπ^{+} and Λ_{c}^{+}→Σ^{0}π^{+} are measured to be (1.31±0.08_{stat}±0.05_{syst})×10^{-2} and (1.22±0.08_{stat}±0.07_{syst})×10^{-2}, respectively, which are consistent with previous results.

[Acute-on-chronic liver failure: definition, diagnosis, and pathogenesis]

Acute-on-chronic liver failure (ACLF) is a form of complex syndrome with acute deterioration of liver function that occurs on the basis of chronic liver disease, and is accompanied by hepatic and extrahepatic organ failure with high mortality rate. The short-term mortality rate of comprehensive internal medicine treatment is as high as 50%-90%. This paper summarizes the current common definitions and diagnostic criteria, early-warning prediction models, and pathogenesis of ACLF.

[Impact of neoadjuvant immunotherapy on pulmonary function and perioperative outcomes in patients with resectable non-small cell lung cancer]

Objective: To explore the effect of neoadjuvant immunotherapy on pulmonary function and the efficacy in patients with resectable non-small cell lung cancer. Methods: Data of 30 patients with non-small cell lung cancer (NSCLC) who received neoadjuvant immunotherapy before surgery in the Chest Hospital of Shanghai Jiaotong University from March 2018 to September 2021 were retrospectively collect. The efficacy and safety of neoadjuvant immunotherapy in the perioperative period and changes in pulmonary function of patients before and after neoadjuvant treatment were valuated. Results: The patients were all-male with age of (61±8)years old, The major pathological response (MPR) rate of patients receiving neoadjuvant immunotherapy was 43%(13 cases), the pathologic complete response (pCR) rate was 37% (11 cases), disease control rate (DCR) was 97% (29 cases), objective response rate (ORR) was 67% (20 cases). The forced expiratory volume in one second (FEV1) after treatment was (2.59±0.63) L, and the ratio of FEV1 to the predicted value (FEV1%pred) was 85.27%±15.86%, which were significantly higher than those before treatment [(2.48±0.59)L, 81.73%±15.94%, respectively] (P=0.013, 0.022, respectively). Forced vital capacity (FVC) after treatment was (3.59±0.77) L, which was also significantly higher than before [(3.47±0.76) L,P=0.036]; while there were no statistical difference in FEV1/FVC and FVC accounted for the proportion of predicted values (FVC%pred) between before and after treatment (P=0.084, 0.344, respectively). The ratio of carbon monoxide dispersion (DLCO) to the predicted value (DLCO%pred) decreased from 83.61%±13.10% to 78.69%±13.85% after treatment (P=0.023). There was no significant difference in the incidence of postoperative complications between the DLCO%pred decreased group and the non-decreased group (3/18 vs 0/6; P=0.546). Conclusions: Neoadjuvant immunotherapy can increase the rate of MPR and PCR, significantly increase FEV1 and FEV1%pred, but also lead to a decrease in DLCO%pred; neoadjuvant immunotherapy does not increase the incidence of postoperative complications.

Measurement of the Cross Section for e^{+}e^{-}→Hadrons at Energies from 2.2324 to 3.6710 GeV

Based on electron-positron collision data collected with the BESIII detector operating at the Beijing Electron-Positron Collider II storage rings, the value of R≡σ(e^{+}e^{-}→hadrons)/σ(e^{+}e^{-}→μ^{+}μ^{-}) is measured at 14 center-of-mass energies from 2.2324 to 3.6710 GeV. The resulting uncertainties are less than 3.0% and are dominated by systematic uncertainties.

[Clinical analysis of 81 cases of intravenous leiomyomatosis confined to pelvic cavity]

Objective: To investigate the clinical features, treatment and recurrence factors of intravenous leiomyomatosis (IVL) confined to the pelvic cavity after the operation. Methods: The clinical data of 81 patients who underwent surgery and were pathologically diagnosed with IVL at Women's Hospital, School of Medicine, Zhejiang University from January 2014 to March 2021, were analyzed retrospectively to explore the influencing factors of postoperative recurrence of IVL, including age, gravidity and parity, surgical methods, intraoperative conditions and so on. Results: (1) Clinical features: the age of 81 IVL patients was (43.9±8.1) years old; increased menstrual volume in 26 cases (32%, 26/81), prolonged menstrual period in 31 cases (38%, 31/81), frequency and urgency to urinate in 4 cases (5%, 4/81), abdominal pain and abdominal distension in 8 cases (10%, 8/81), and pelvic masses in 34 cases (42%, 34/81). IVL was diagnosed right in 4 of 72 patients (6%, 4/72) underwent preoperative ultrasound, right in 11 of 51 patients (22%, 11/51) underwent magnetic resonance imaging (MRI), and right in 4 of 19 patients (4/19) underwent CT. (2) Treatment: all patients with IVL underwent surgical treatment. Surgical procedure: myomectomy in 37 cases, total hysterectomy and bilateral salpingectomy in 19 cases, total hysterectomy and bilateral salpingo-ophorectomy in 25 cases. Surgical approach: hysteroscopic operation in 6 cases, transabdominal operation in 52 cases, laparoscopic operation in 23 cases. Fifty-three cases underwent rapid intraoperative pathological examination, 17 cases (32%, 17/53) of them were diagnosed right as IVL. (3) Influencing factors of IVL postoperative recurrence: among 81 patients with IVL, 3 cases were lost to follow-up, and 8 cases (10%, 8/78) had recurrence during follow-up. Age<35 years, number of pregnancies<2, number of births<2, number of fibroids ≥10, abnormal appearance of fibroids (long, vermicular, beadlike, cystic, etc.) and IVL invasion into adjacent vessels were all the risk factors influencing postoperative recurrence of IVL (all P<0.05). Methods of operation, ovariectomy or not, IVL invasion or not, maximum diameter of IVL, abundant blood vessels near uterine fibroids were not associated with postoperative recurrence of IVL (all P>0.05). Conclusions: The clinical manifestations and preoperative auxiliary examination of IVL are lack of specificity. Doctors need to pay attention to young patients with uterine fibroids, and choose the appropriate surgical scope when the characteristic manifestations of IVL be found during the operation, or the right diagnoses of IVL in the surgery's rapid intraoperative pathology be examined, and should remove the IVL lesions to reduce the recurrence as far as possible.

First Measurement of Polarizations in the Decay D^{0}→ωφ

Using a data sample corresponding to an integrated luminosity of 2.93  fb^{-1} collected at a center-of-mass energy sqrt[s]=3.773  GeV by the BESIII detector, the decay D^{0}→ωϕ is observed for the first time. The branching fraction is measured to be (6.48±0.96±0.40)×10^{-4} with a significance of 6.3σ, where the first and second uncertainties are statistical and systematic, respectively. An angular analysis reveals that the ϕ and ω mesons from the D^{0}→ωϕ decay are transversely polarized. The 95% confidence level upper limit on longitudinal polarization fraction is set to be less than 0.24, which is inconsistent with current theoretical expectations and challenges our understanding of the underlying dynamics in charm meson decays.

Periodicities in the Daily Proton Fluxes from 2011 to 2019 Measured by the Alpha Magnetic Spectrometer on the International Space Station from 1 to 100 GV

We present the precision measurement of the daily proton fluxes in cosmic rays from May 20, 2011 to October 29, 2019 (a total of 2824 days or 114 Bartels rotations) in the rigidity interval from 1 to 100 GV based on 5.5×10^{9} protons collected with the Alpha Magnetic Spectrometer aboard the International Space Station. The proton fluxes exhibit variations on multiple timescales. From 2014 to 2018, we observed recurrent flux variations with a period of 27 days. Shorter periods of 9 days and 13.5 days are observed in 2016. The strength of all three periodicities changes with time and rigidity. The rigidity dependence of the 27-day periodicity is different from the rigidity dependences of 9-day and 13.5-day periods. Unexpectedly, the strength of 9-day and 13.5-day periodicities increases with increasing rigidities up to ∼10  GV and ∼20  GV, respectively. Then the strength of the periodicities decreases with increasing rigidity up to 100 GV.

Measurement of the Absolute Branching Fraction of D_{s}^{+}→τ^{+}ν_{τ} via τ^{+}→e^{+}ν_{e}ν[over ¯]_{τ}

Using a dataset of 6.32  fb^{-1} of e^{+}e^{-} annihilation data collected with the BESIII detector at center-of-mass energies between 4178 and 4226 MeV, we have measured the absolute branching fraction of the leptonic decay D_{s}^{+}→τ^{+}ν_{τ} via τ^{+}→e^{+}ν_{e}ν[over ¯]_{τ}, and find B_{D_{s}^{+}→τ^{+}ν_{τ}}=(5.27±0.10±0.12)×10^{-2}, where the first uncertainty is statistical and the second is systematic. The precision is improved by a factor of 2 compared to the previous best measurement. Combining with f_{D_{s}^{+}} from lattice quantum chromodynamics calculations or the |V_{cs}| from the CKMfitter group, we extract |V_{cs}|=0.978±0.009±0.012 and f_{D_{s}^{+}}=(251.1±2.4±3.0)  MeV, respectively. Combining our result with the world averages of B_{D_{s}^{+}→τ^{+}ν_{τ}} and B_{D_{s}^{+}→μ^{+}ν_{μ}}, we obtain the ratio of the branching fractions B_{D_{s}^{+}→τ^{+}ν_{τ}}/B_{D_{s}^{+}→μ^{+}ν_{μ}}=9.72±0.37, which is consistent with the standard model prediction of lepton flavor universality.

Direct Measurement of the Astrophysical ^{19}F(p,αγ)^{16}O Reaction in the Deepest Operational Underground Laboratory

Fluorine is one of the most interesting elements in nuclear astrophysics, where the ^{19}F(p,α)^{16}O reaction is of crucial importance for Galactic ^{19}F abundances and CNO cycle loss in first generation Population III stars. As a day-one campaign at the Jinping Underground Nuclear Astrophysics experimental facility, we report direct measurements of the essential ^{19}F(p,αγ)^{16}O reaction channel. The γ-ray yields were measured over E_{c.m.}=72.4-344  keV, covering the Gamow window; our energy of 72.4 keV is unprecedentedly low, reported here for the first time. The experiment was performed under the extremely low cosmic-ray-induced background environment of the China JinPing Underground Laboratory, one of the deepest underground laboratories in the world. The present low-energy S factors deviate significantly from previous theoretical predictions, and the uncertainties are significantly reduced. The thermonuclear ^{19}F(p,αγ)^{16}O reaction rate has been determined directly at the relevant astrophysical energies.

Erratum: Properties of a New Group of Cosmic Nuclei: Results from the Alpha Magnetic Spectrometer on Sodium, Aluminum, and Nitrogen [Phys. Rev. Lett. 127, 021101 (2021)]

This corrects the article DOI: 10.1103/PhysRevLett.127.021101.

Observation of D^{0}→K_{1}(1270)^{-}e^{+}ν_{e}

Using 2.93  fb^{-1} of e^{+}e^{-} collision data taken with the BESIII detector at a center-of-mass energy of 3.773 GeV, the observation of the D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} semileptonic decay is presented. The statistical significance of the decay D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} is greater than 10σ. The branching fraction of D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} is measured to be (1.09±0.13_{-0.16}^{+0.09}±0.12)×10^{-3}. Here, the first uncertainty is statistical, the second is systematic, and the third originates from the assumed branching fraction of K_{1}(1270)^{-}→K^{-}π^{+}π^{-}. The fraction of longitudinal polarization in D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} is determined for the first time to be 0.50±0.19_{stat}±0.08_{syst}.

First Measurement of the Absolute Branching Fraction of Λ→pμ^{-}ν[over ¯]_{μ}

The absolute branching fraction of Λ→pμ^{-}ν[over ¯]_{μ} is reported for the first time based on an e^{+}e^{-} annihilation sample of 10×10^{9}  J/ψ events collected with the BESIII detector at sqrt[s]=3.097  GeV. The branching fraction is determined to be B(Λ→pμ^{-}ν[over ¯]_{μ})=[1.48±0.21(stat)±0.08(syst)]×10^{-4}, which is improved by about 30% in precision over the previous indirect measurements. Combining this result with the world average of B(Λ→pe^{-}ν[over ¯]_{e}), we obtain the ratio {[Γ(Λ→pμ^{-}ν[over ¯]_{μ})]/[Γ(Λ→pe^{-}ν[over ¯]_{e})]} to be 0.178±0.028, which agrees with the standard model prediction assuming lepton flavor universality. The asymmetry of the branching fractions of Λ→pμ^{-}ν[over ¯]_{μ} and Λ[over ¯]→p[over ¯]μ^{+}ν_{μ} is also determined, and no evidence for CP violation is found.

Direct Measurement of the Branching Fractions B(ψ(3686)→J/ψX) and B(ψ(3770)→J/ψX), and Observation of the State R(3760) in e^{+}e^{-}→J/ψX

We report a measurement of the observed cross sections of e^{+}e^{-}→J/ψX based on 3.21  fb^{-1} of data accumulated at energies from 3.645 to 3.891 GeV with the BESIII detector operated at the BEPCII collider. In analysis of the cross sections, we measured the decay branching fractions of B(ψ(3686)→J/ψX)=(64.4±0.6±1.6)% and B(ψ(3770)→J/ψX)=(0.5±0.2±0.1)% for the first time. The energy-dependent line shape of these cross sections cannot be well described by two Breit-Wigner (BW) amplitudes of the expected decays ψ(3686)→J/ψX and ψ(3770)→J/ψX. Instead, it can be better described with one more BW amplitude of the decay R(3760)→J/ψX. Under this assumption, we extracted the R(3760) mass M_{R(3760)}=3766.2±3.8±0.4  MeV/c^{2} , total width Γ_{R(3760)}^{tot}=22.2±5.9±1.4  MeV, and product of leptonic width and decay branching fraction Γ_{R(3760)}^{ee}B[R(3760)→J/ψX]=(79.4±85.5±11.7)  eV. The significance of the R(3760) is 5.3σ. The first uncertainties of these measured quantities are from fits to the cross sections and second systematic.

Influence of lens position as detected by an anterior segment analysis system on postoperative refraction in cataract surgery

AIM

To predict postoperative intraocular lens (IOL) position using the Sirius anterior segment analysis system and investigate the effect of lens position and IOL type on postoperative refraction.

METHODS

A total of 97 patients (102 eyes) were enrolled in the final analysis. An anterior segment biometry measurement was performed preoperatively with Sirius and Lenstar. The results of predicted lens position (PLP) and IOL power were automatically calculated by the software used by the instruments. Effective lens position (ELP) was measured manually using Sirius 3mo postoperatively. Pearson's correlation analysis and linear regression analysis were used to determine the correlation of lens position to other parameters.

RESULTS

PLP and ELP were positively correlated to axial length (AL; r=0.42, P<0.0001 and r=0.49, P<0.0001, respectively). There was a weak correlation between the peLP (ELP-PLP) and the prediction error of spherical refraction (peSR; r=0.34, P<0.0001). The peLP of Softec HD IOL differed statistically from those of both the TECNIS ZCB00 and Sensor AR40E IOLs. Multiple linear regression was used to obtain the prediction formula: ELP=0.66+0.63×[aqueous depth (AQD)+0.6LT] (r=0.61, P<0.0001), and a new variable (AQD+0.6 LT) was found to have the strongest correlation with ELP.

CONCLUSION

The Sirius anterior segment analysis system is helpful to predict ELP, which reduces postoperative refraction error.

Properties of a New Group of Cosmic Nuclei: Results from the Alpha Magnetic Spectrometer on Sodium, Aluminum, and Nitrogen

We report the properties of sodium (Na) and aluminum (Al) cosmic rays in the rigidity range 2.15 GV to 3.0 TV based on 0.46 million sodium and 0.51 million aluminum nuclei collected by the Alpha Magnetic Spectrometer experiment on the International Space Station. We found that Na and Al, together with nitrogen (N), belong to a distinct cosmic ray group. In this group, we observe that, similar to the N flux, both the Na flux and Al flux are well described by the sums of a primary cosmic ray component (proportional to the silicon flux) and a secondary cosmic ray component (proportional to the fluorine flux). The fraction of the primary component increases with rigidity for the N, Na, and Al fluxes and becomes dominant at the highest rigidities. The Na/Si and Al/Si abundance ratios at the source, 0.036±0.003 for Na/Si and 0.103±0.004 for Al/Si, are determined independent of cosmic ray propagation.

Photoinduced multistage phase transitions in Ta2NiSe5

Ultrafast control of material physical properties represents a rapidly developing field in condensed matter physics. Yet, accessing the long-lived photoinduced electronic states is still in its early stages, especially with respect to an insulator to metal phase transition. Here, by combining transport measurement with ultrashort photoexcitation and coherent phonon spectroscopy, we report on photoinduced multistage phase transitions in Ta2NiSe5. Upon excitation by weak pulse intensity, the system is triggered to a short-lived state accompanied by a structural change. Further increasing the excitation intensity beyond a threshold, a photoinduced steady new state is achieved where the resistivity drops by more than four orders at temperature 50 K. This new state is thermally stable up to at least 350 K and exhibits a lattice structure different from any of the thermally accessible equilibrium states. Transmission electron microscopy reveals an in-chain Ta atom displacement in the photoinduced new structure phase. We also found that nano-sheet samples with the thickness less than the optical penetration depth are required for attaining a complete transition.

Observation of a Near-Threshold Structure in the K^{+} Recoil-Mass Spectra in e^{+}e^{-}→K^{+}(D_{s}^{-}D^{*0}+D_{s}^{*-}D^{0})

We report a study of the processes of e^{+}e^{-}→K^{+}D_{s}^{-}D^{*0} and K^{+}D_{s}^{*-}D^{0} based on e^{+}e^{-} annihilation samples collected with the BESIII detector operating at BEPCII at five center-of-mass energies ranging from 4.628 to 4.698 GeV with a total integrated luminosity of 3.7  fb^{-1}. An excess of events over the known contributions of the conventional charmed mesons is observed near the D_{s}^{-}D^{*0} and D_{s}^{*-}D^{0} mass thresholds in the K^{+} recoil-mass spectrum for events collected at sqrt[s]=4.681  GeV. The structure matches a mass-dependent-width Breit-Wigner line shape, whose pole mass and width are determined as (3982.5_{-2.6}^{+1.8}±2.1)  MeV/c^{2} and (12.8_{-4.4}^{+5.3}±3.0)  MeV, respectively. The first uncertainties are statistical and the second are systematic. The significance of the resonance hypothesis is estimated to be 5.3  σ over the contributions only from the conventional charmed mesons. This is the first candidate for a charged hidden-charm tetraquark with strangeness, decaying into D_{s}^{-}D^{*0} and D_{s}^{*-}D^{0}. However, the properties of the excess need further exploration with more statistics.

Model-Independent Determination of the Spin of the Ω^{-} and Its Polarization Alignment in ψ(3686)→Ω^{-}Ω[over ¯]^{+}

We present an analysis of the process ψ(3686)→Ω^{-}Ω[over ¯]^{+} (Ω^{-}→K^{-}Λ, Ω[over ¯]^{+}→K^{+}Λ[over ¯], Λ→pπ^{-}, Λ[over ¯]→p[over ¯]π^{+}) based on a dataset of 448×10^{6}  ψ(3686) decays collected with the BESIII detector at the BEPCII electron-positron collider. The helicity amplitudes for the process ψ(3686)→Ω^{-}Ω[over ¯]^{+} and the decay parameters of the subsequent decay Ω^{-}→K^{-}Λ (Ω[over ¯]^{+}→K^{+}Λ[over ¯]) are measured for the first time by a fit to the angular distribution of the complete decay chain, and the spin of the Ω^{-} is determined to be 3/2 for the first time since its discovery more than 50 years ago.