Observation of a_{0}^{0}(980)-f_{0}(980) Mixing

We report the first observation of a_{0}^{0}(980)-f_{0}(980) mixing in the decays of J/ψ→ϕf_{0}(980)→ϕa_{0}^{0}(980)→ϕηπ^{0} and χ_{c1}→a_{0}^{0}(980)π^{0}→f_{0}(980)π^{0}→π^{+}π^{-}π^{0}, using data samples of 1.31×10^{9}  J/ψ events and 4.48×10^{8}  ψ(3686) events accumulated with the BESIII detector. The signals of f_{0}(980)→a_{0}^{0}(980) and a_{0}^{0}(980)→f_{0}(980) mixing are observed at levels of statistical significance of 7.4σ and 5.5σ, respectively. The corresponding branching fractions and mixing intensities are measured and the constraint regions on the coupling constants, g_{a_{0}K^{+}K^{-}} and g_{f_{0}K^{+}K^{-}}, are estimated. The results improve the understanding of the nature of a_{0}^{0}(980) and f_{0}(980).

Precision Study of η^{'}→γπ^{+}π^{-} Decay Dynamics

Using a low background data sample of 9.7×10^{5}  J/ψ→γη^{'}, η^{'}→γπ^{+}π^{-} events, which are 2 orders of magnitude larger than those from the previous experiments, recorded with the BESIII detector at BEPCII, the decay dynamics of η^{'}→γπ^{+}π^{-} are studied with both model-dependent and model-independent approaches. The contributions of ω and the ρ(770)-ω interference are observed for the first time in the decays η^{'}→γπ^{+}π^{-} in both approaches. Additionally, a contribution from the box anomaly or the ρ(1450) resonance is required in the model-dependent approach, while the process specific part of the decay amplitude is determined in the model-independent approach.

[Usefulness of the residual SYNTAX score to predict long term outcome in acute coronary syndrome patients underwent percutaneous coronary intervention]

Objective: To quantify the extent and complexity of residual coronary stenosis following PCI by the residual SYNTAX score, and to evaluate its impact on adverse ischemic outcomes in acute coronary syndrome(ACS) patients. Methods: From January 2013 to December 2013, a total of 1 414 consecutive moderate- and high-risk ACS patients who underwent any PCI with multi-vessel coronary artery disease were evaluated.Patients were stratified by rSS quartiles and their outcomes were compared. Results: The rSS was 4.8±6.7. 591 patients (41.8%) had rSS=0(CR), 233 patients (16.5%) had rSS>0 but ≤ 3, 296 patients (20.9%) had rSS>3 but ≤8 and 294 patients (20.8%) had rSS>8.Clinical risk factors were more frequent in patients with incomplete revascularization(IR) compared with complete revascularization(CR). The 2-year rates of all-caused death(1.2% vs 0.4%, 2.0%, 4.4%, P=0.003), cardiac death, revascularization and MACCE were significantly higher in high rSS group, compared to other groups.By multivariable analysis, rSS was a strong independent predictor of ischemic outcomes at 2-year, including all-cause mortality (HR=1.05, 95%CI 1.01-1.09, P=0.019), cardiac death, revascularization and MACCE. Conclusions: The rSS is a strong independent predictor of all-caused death, cardiac death, revascularization and MACCE and has moderated predictive ability for those ischemic outcomes.

[Impact of direct bilirubin on the long-term outcome of patients with acute coronary syndrome post percutaneous coronary intervention]

Objective: To investigate the impact of direct bilirubin on long-term prognosis of acute coronary syndrome (ACS) patients post percutaneous coronary intervention(PCI). Methods: As a prospective and observational cohort study, a total of 6 431 consecutive ACS patients underwent PCI from January to December 2013 in Fuwai hospital were included. Patients were divided into 3 groups according to tertiles values of direct bilirubin as follows: low direct bilirubin group(<2.2 μmol/L, n=2 219), moderate direct bilirubin group(2.2-3.0 μmol/L, n=2 016), and high direct bilirubin group(>3 μmol/L, n=2 196). The clinical characteristics were compared among the 3 groups, and the impact of direct bilirubin on clinical adverse events (main adverse cardiovascular and cerebrovascular events included cardiogenic death, myocardial infarction, revascularization, stroke, and stent thrombosis) were analyzed at 2 years after PCI. Results: (1) Percent of male patients was 66.5%(1 475/2 219), 78.0%(1 572/2 016), and 86.2%(1 892/2 196), body mass index was(25.7±3.1), (26.0±3.3),and (26.0±3.2) kg/m(2), the ratio of the history of old myocardial infarction was 11.9%(264/2 219), 13.0%(263/2 016),and 14.9%(328/2 196), the ratio of the current smoker was 56.3%(1 249/2 219), 59.1%(1 192/2 016),and 60.0%(1 317/2 196) in low, moderate and high direct bilirubin groups respectively, and the differences were statistically significant (P<0.01 or 0.05). (2) Two years after PCI, the all-cause mortality was 0.8%(17/2 219), 1.8%(36/2 016), and 1.5%(33/2 196) (P=0.011),the cardiogenic mortality was 0.5%(12/2 219), 1.3%(26/2 016), and 0.6%(13/2 196) (P=0.010),the ratio of myocardial infarction was 2.2%(49/2 219), 2.4%(49/2 016), and 1.4%(31/2 196)(P=0.044),the ratio of revascularization was 8.8%(195/2 219), 8.3%(168/2 016),and 8.9%(196/2 196)(P=0.783),the ratio of stroke was 1.4%(30/2 219),1.1%(22/2 016), and 1.9%(42/2 196)(P=0.076),the ratio of stent thrombosis was 0.9%(19/2 219), 1.2%(24/2 016),and 0.7%(15/2 196)(P=0.210) in low, moderate and high direct bilirubin groups, respectively. (3) Multivariable Cox regression analysis showed that, patients in moderate direct bilirubin group faced increased the risk of all-cause mortality compared with patients in the low direct bilirubin group (HR=2.23, 95%CI 1.23-4.05, P= 0.009), and the risk of all-cause mortality was similar between high direct bilirubin group and low direct bilirubin group (HR=1.84, 95%CI 0.99-3.38, P= 0.051). There were no statistically significant difference in the risks of main adverse cardiovascular and cerebrovascular events,cardiogenic death, myocardial infarction, revascularization, stroke, and stent thrombosis in moderate and high direct bilirubin groups compared with low direct bilirubin group (all P>0.05). Conclusion: Moderate direct bilirubin level is associated with increased risk of all-cause death at 2 years after PCI compared with low level of direct bilirubin group.

Precision Measurement of the e^{+}e^{-}→Λ_{c}^{+}Λ[over ¯]_{c}^{-} Cross Section Near Threshold

The cross section of the e^{+}e^{-}→Λ_{c}^{+}Λ[over ¯]_{c}^{-} process is measured with unprecedented precision using data collected with the BESIII detector at sqrt[s]=4574.5, 4580.0, 4590.0 and 4599.5 MeV. The nonzero cross section near the Λ_{c}^{+}Λ[over ¯]_{c}^{-} production threshold is cleared. At center-of-mass energies sqrt[s]=4574.5 and 4599.5 MeV, the higher statistics data enable us to measure the Λ_{c} polar angle distributions. From these, the Λ_{c} electric over magnetic form-factor ratios (|G_{E}/G_{M}|) are measured for the first time. They are found to be 1.14±0.14±0.07 and 1.23±0.05±0.03, respectively, where the first uncertainties are statistical and the second are systematic.

[Predictive value of GRACE discharge score for long-term out-of-hospital death in acute coronary syndrome after percutaneous coronary intervention]

Objective: To evaluate the prognostic value of Global Registry of Acute Coronary Events(GRACE) discharge score for long-term out-of-hospital death in acute coronary syndrome (ACS) after drug-eluting stents (DES) and with Dual-antiplatelet Therapy (DAPT). Methods: Our study was a prospective, observational, single center (Fuwai Hospital of China) study.A total of 6 431consecutive ACS patients underwent percutaneous coronary intervention(PCI)between January 2013 and December 2013 were involved.The primary endpoint was all-cause death and second endpoint was major adverse cardiovascular and cerebrovascular events (MACCE) as a composite of all-cause death, myocardial infarction, revascularization, stent thrombosis or stroke. Results: Finally, 5 867 ACS patients who were received DES with DAPT and had no in-hospital event included in this study, and 59 (1.01%) death and 608 (10.36%) MACCE were reported during 2-year follow-up after discharge.GRACE score was significantly higher among death patients than those survivalpatients (94± 28 vs 78± 24, P<0.001). According to risk stratification of GRACE discharge score, as compared to the low-risk group, death risk in high-risk group was 6.73 times (HR=6.73, 95%CI 3.53-12.84; P<0.001) higher, but could not distinguish between the moderate and low risk group (HR=1.61, 95%CI 0.88-2.95; P=0.124). The GRACE score showed predictive value in ACS patients after DESand with DAPT (area under the receiver operating characteristic curve (AUROC)=0.661; 95%CI 0.586-0.736, P<0.001). In subgroup analysis, GRACE score also showed predictive value both in unstable angina pectoris (UAP)(AUROC=0.660, 95%CI 0.576-0.744; P<0.001) and acute myocardial infarction(AMI)subgroup (AUROC=0.748, 95%CI 0.631-0.864; P=0.001). Conclusion: GRACE discharge score shows prognostic value for long-term out-of-hospital death in ACS patients undergoing PCI with DES and DAPT, and demonstrates good risk stratification of high and low-risk of death.

[Study on the difference of binocular accommodative response between atients with intermittent exotropia under different viewing condition]

Objective: To evaluate the accommodative response of patients with intermittent exotropia (IXT) objectively, and study the changes of accommodative response of intermittent exotropia patients when maintaining binocular fusion. Methods: The prospective cohort study was used in this study. Twenty-four patients diagnosed with basic intermittent exotropia who visited the eye hospital of Wenzhou Medical University during October 2016 through January 2017 together with 24 normal volunteers were included, the 48 participants aged from 10 to 27 years old. The participants were divided into the case group and the control group. There were 11 males and 13 females in the case group, and 7 males and 17 females in the control group. The Open-filed autorefractor WAM-5500 (Grand Seiko, Japan) was used to measure the accommodative response of each eye under binocular and monocular viewing conditions at 5 m and 40 cm respectively. During the measurement, patients wore full correction spectacles to achieve distant best-corrected visual acuity of both eyes. The accommodative responses of each eye under binocular and monocular viewing conditions at distance or near between fellow eyes and groups were compared. Results: Under near fixation (40cm) binocular viewing conditions, the accommodative response of the fixating eye (-1.915±0.301)D was different from the deviating eye -1.649(-2.020, -0.304)D in the case group (Z=-3.714, P<0.001). Under near fixation monocular viewing conditions, the accommodative response of the fixating eye (-1.653±0.271)D was also different from the deviating eye -1.565 (-2.031, -0.667)D in the case group (Z=-2.971, P=0.003). During binocular viewing, the asymmetric value of the accommodative response between both eyes of the case group was 0.389(0.102, 1.458)D which was more significant than the normal controls' 0.155(0.009, 0.573)D (Z=-3.505, P<0.001), but during monocular viewing, there was no significant difference between the groups (Z=-1.908, P=0.056). Under near viewing conditions, the variation value of the fixating eyes of the case group was -0.228(-0.796, 0.382)D, which was greater than the variation value -0.086(-0.606, 0.628)D of the right eye of the normal controls, such difference is of statistical significance (Z=-2.279, P=0.023). Under distance viewing conditions, there was no significant difference in the accommodative response between fixating eyes and deviating eyes in case group neither during monocular viewing nor binocular viewing (t=-1.525, -1.729, P>0.05). Besides, the asymmetric values of accommodative response between groups were not significantly different (Z=-1.433, P=0.152. Z=-0.938, P=0.348). Under distance viewing conditions, the changes in accommodative response of each eye during both monocular viewing and binocular viewing were not significantly different between case group and normal controls (Z=-0.041, P=0.967. Z=-1.433, P=0.152). Conclusions: The accommodative responses of the fixating eye and deviating eye of patients with intermittent exotropia were asymmetric under near fixation binocular viewing conditions, and the accommodative response of the deviating eye tends to decrease. Besides, the change of accommodative response of the patients with intermittent exotropia when maintaining binocular fusion is more significant than that of the normal controls. (Chin J Ophthalmol, 2018, 54: 55-61).

[Outcome of patients with coronary artery disease and left ventricular ejection fraction less than 50% undergoing percutaneous coronary intervention]

Objective: To investigate the in-hospital and long-term outcomes of patients with left ventricular ejection fraction (LVEF) <50% undergoing percutaneous coronary intervention (PCI) . Methods: From January to December 2013, 10 445 consecutive patients who underwent PCI in Fuwai Hospital and the LVEF value was available were prospectively included. The patients were divided into LVEF≥50% group (9 896 cases) and LVEF<50% group (549 cases) . The in-hospital and 2-year clinical outcomes were compared between the 2 groups. The association between LVEF<50% and clinical outcomes was assessed using multivariable Cox regression analysis. Results: (1) Compared with LVEF ≥50% group, LVEF< 50% group had higher rates of in-hospital all-cause death (1.1% (6/549) vs. 0.2% (17/9 896) , P<0.01) , cardiac death (1.1% (6/549) vs. 0.1% (12/9 896) , P<0.01) , in-stent thrombosis (0.7% (4/549) vs. 0.2% (18/9 896) , P<0.01) , myocardial infarction (2.4% (13/549) vs. 1.2% (121/9 896) , P<0.05) ,and major adverse cardiovascular and cerebrovascular events (MACCE) which including death, myocardial infarction, revascularization, in-stent thrombosis, and stroke (3.6% (20/549) vs. 1.4% (137/9 896) , P<0.01) . (2) A total of 10 388 (99.5%) patients completed 2-year follow-up. Compared with LVEF ≥50% group, LVEF<50% group had higher rates of 2-year all-cause death (4.7% (26/549) vs. 1.0% (101/9 896) , P<0.01) , cardiac death (4.0% (22/549) vs. 0.5% (50/9 896) , P<0.01) , in-stent thrombosis (3.1% (17/549) vs. 0.7% (71/9 896) , P<0.001) , myocardial infarction (4.2% (23/549) vs. 1.9% (186/9 896) , P<0.01) ,and MACCE (17.9% (98/549) vs. 11.8% (1 172/9 896) , P<0.01) . There were no significant differences on the rates of 2-year target-vessel revascularization, bleeding and stroke between the two groups. (3) The multivariable Cox regression analysis demonstrated that LVEF< 50% was the independent risk factor of 2-year all-cause death (HR=2.47, 95%CI 1.49-4.08, P<0.01) , cardiac death (HR=3.25, 95%CI 1.79-5.90, P<0.01) , in-stent thrombosis (HR=4.19, 95%CI 2.39-7.34, P<0.01) , myocardial infarction (HR=2.00, 95%CI 1.26-3.16, P<0.01) , and MACCE (HR=1.40, 95%CI 1.13-1.74, P<0.01) . (4) After propensity score matching, all in-hospital outcomes were similar between the two groups, including all-cause death, cardiac death, in-stent thrombosis, myocardial infarction, revascularization, bleeding, stroke, and MACCE (all P>0.05) . After propensity score matching,the multivariable Cox regression analysis demonstrated that LVEF<50% was still an independent risk factor of 2-year all-cause death (HR=3.08, 95%CI 1.37-6.89, P<0.01) , cardiac death (HR= 4.12, 95%CI 1.53-11.07, P<0.01) ,and in-stent thrombosis (HR=3.82, 95%CI 1.27-11.5, P<0.05) . Conclusion: LVEF< 50% is an independent risk factor of 2-year all-cause death, cardiac death, and in-stent thrombosis in patients undergoing PCI, but it does not increase the risk of target-vessel revascularization, bleeding or stroke.

[Efficacy comparison of 3 strategies for real-world stable coronary artery disease patients with three-vessel disease]

Objective: To compare the effectiveness of percutaneous coronary intervention (PCI), coronary artery bypass grafting (CABG) or medical therapy (MT) alone for real-world stable coronary artery disease (SCAD) patients with three-vessel disease (TVD) in mainland China. Methods: A total of 8 943 consecutive cases with TVD hospitalized in our center from April 2004 to February 2011 were screened for this study. In this cohort, 3 435 cases diagnosed as SCAD were analyzed. PCI, CABG, MT alone were performed in 1 313 (38.2%), 1 259 (36.7%) and 863 (25.1%) patients, respectively. Propensity score matching (PSM) analysis using nearest neighbor matching with a 1∶1 ratio was applied, and 758 pairs of CABG and PCI groups, 552 pairs of PCI and MT groups, 639 pairs of CABG and MT groups were selected, respectively. 1- and 2-year clinical outcomes were evaluated among PCI, CABG and MT group. Kaplan-Meier curves and multivariable Cox regression method were used for survival analysis. Results: Significant differences were found at baseline between PCI, CABG and MT group, including age, gender, body mass index, family history of coronary artery disease, hyperlipidemia, diabetes mellitus, previous myocardial infarction, stroke, previous revascularization, peripheral vascular disease, SNYTAX score, left ventricular ejection fraction, hemoglobin, serum creatinine, high-sensitivity C-reactive protein, triglyceride and medication (all P<0.05) . All-cause death rates of 1- and 2-year follow-up of PCI, CABG and MT group were 0.6% (8/1 313), 1.1% (14/1 259), 3.4% (29/863) (P<0.001) and 1.1%(14/1 313), 1.5%(19/1 259), 7.3%(63/863) (P<0.001), respectively. Multivariate Cox regression analysis showed that 1-year MACCE rate (HR=0.51, 95%CI 0.33-0.77, P=0.001) was significantly reduced, due to the significant decrease of myocardial infarction (MI) rate (HR=0.09, 95%CI 0.01-0.76, P=0.027) and repeat revascularization rate (HR=0.21, 95%CI 0.10-0.41, P<0.001) in CABG group compared to PCI group, while all-cause death (HR=1.21, 95%CI 0.48-3.00, P=0.69) and stroke rate (HR=2.31, 95%CI 0.82-6.47, P=0.112) were similar between 2 groups. 2-year outcome showed CABG was associated with higher stroke rate (HR=2.20, 95%CI 1.06-4.55, P=0.034) and lower MI (HR=0.19, 95%CI 0.06-0.59, P=0.004) and repeat revascularization rate (HR=0.22, 95%CI 0.13-0.37, P<0.001), and lower MACCE rate (HR=0.49, 95%CI 0.36-0.68, P<0.001). Compared to MT group, 2-year all-cause death (HR=0.22, 95%CI 0.12-0.42, P<0.001) and MACCE rate (HR=0.63, 95%CI 0.47-0.83, P=0.001) were lower in PCI group, while 2-year all-cause death (HR=0.21, 95%CI 0.13-0.37, P<0.001), MACCE (HR=0.31, 95%CI 0.23-0.42, P<0.001), MI (HR=0.19, 95%CI 0.06-0.60, P=0.004) and repeat revascularization rate (HR=0.24, 95%CI 0.13-0.41, P<0.001) were lower in CABG group. Results of multivariate Cox regression analysis after PSM were consistent with above results. Conclusion: For SCAD patients with TVD, CABG shows better effectiveness by reducing MI and revascularization risk as compared to PCI, even though stroke risk is somehow higher in CABG patients. Patients received MT alone are associated with worse outcomes than those undergoing revascularization strategies.

[Clinical characteristics and prognosis in the patients of stroke after percutaneous coronary intervention]

Objective: To investigate the clinical characteristics and prognosis in patients with stroke after percutaneous coronary intervention (PCI). Methods: From January 2013 to December 2013, 10 724 consecutive patients undergoing PCI including acute coronary syndrome and stable angina pectoris were enrolled.A two years' follow up was conducted among these patients to investigate the clinical characteristics and prognosis of patients with stroke and of those without. A comparison was done between the two groups. Results: One hundred and forty-five patients had stroke (1.4%) during the follow-up period after PCI, including 124 cases with ischemic stroke (1.2%), out of whom 4 (3.2%) patients died; 21 cases with hemorrhagic stroke, out of whom 9 patients (42.9%) died.There was more female, and more patients with risks factors, hypertension, previous myocardial infarction, previous stroke, etc. in the patients with stroke.During the 2-year follow-up, patients with stroke experienced higher incidence of all-cause mortality (9% vs 1.1%, P<0.000 1). There were no significant differences in the incidences of cardiac death, myocardial infarction, revascularization, stent thrombosis and major adverse cardiovascular event rates between the two groups.COX regression analysis showed that stroke after PCI was associated with the increased mortality (HR=8.387, 95%CI: 4.725-14.855, P<0.000 1). Meanwhile, after propensity score matched analyses (129 pairs), the trend was not changed, and stroke was still an independent risk factor of all-cause mortality (HR=6.737, 95%CI: 1.52-29.85, P=0.012). Conclusions: The patients underwent PCI, who had stroke later, had more clinical risk factors, and more serious degree of atherosclerosis.The incidence of stroke is an independent risk factor for all-cause mortality in patients with coronary heart disease after PCI.

[Impact of platelet distribution width on the extent and long-term outcome of patients with stable coronary artery disease post percutaneous coronary intervention]

Objective: To evaluate the relationship between platelet distribution width(PDW) and the extent of coronary artery disease and 2-year outcome in patients received percutaneous coronary artery intervention(PCI) because of stable coronary artery disease(SCAD). Methods: We consecutively enrolled 4 293 patients who received PCI because of SCAD in Fuwai Hospital from Jan 2013 to Dec 2013, patients were followed up for 2 years. Patients were divided into three groups according to tertiles values of PDW as follows: PDW≤11.4%(1 402 patients), 11.4%<PDW≤12.9%(1 441 patients) and PDW>12.9% (1 450 patients). Major adverse cardiovascular and cerebrovascular events (MACCE) were defined as the occurrence of death, myocardial infarction, target vessel revascularization, intra stent thrombosis and stroke during follow-up. Multivariable logistic regression was used to evaluate the relationship between PDW and the extent of CAD. Multivariable Cox regression was used to evaluate the relationship between PDW and prognosis of SCAD patients. Results: PDW was associated with diabetes mellitus, body mass index, red cell distribution width, mean platelet volume (MPV), platelet counts and glycosylated haemoglobin (P<0.05), but not associated with age, sex, estimated glomerular filtration rate (P>0.05). PDW was not correlated with the extent of CAD(P=0.990), SYNTAX score(P=0.721), no-reflow phenomenon after PCI(P=0.978). Multivariable logistic regression also showed no relationship between PDW and extent of CAD (OR=0.994, 95%CI 0.961-1.029, P=0.73). PDW was found to be an independent risk factor of 2-year cardiac death (HR=1.242, 95%CI 1.031-1.497, P=0.022), but was not an independent risk factor of all-cause death and MACCE. Conclusions: PDW is not related with the extent of coronary artery disease. PDW is an independent risk factor of 2-year cardiac death, but is not an independent risk factor of all-cause death and MACCE in this patient cohort.

Determination of the Spin and Parity of the Z_{c}(3900)

The spin and parity of the Z_{c}(3900)^{±} state are determined to be J^{P}=1^{+} with a statistical significance larger than 7σ over other quantum numbers in a partial wave analysis of the process e^{+}e^{-}→π^{+}π^{-}J/ψ. We use a data sample of 1.92  fb^{-1} accumulated at sqrt[s]=4.23 and 4.26 GeV with the BESIII experiment. When parametrizing the Z_{c}(3900)^{±} with a Flatté-like formula, we determine its pole mass M_{pole}=(3881.2±4.2_{stat}±52.7_{syst})  MeV/c^{2} and pole width Γ_{pole}=(51.8±4.6_{stat}±36.0_{syst})  MeV. We also measure cross sections for the process e^{+}e^{-}→Z_{c}(3900)^{+}π^{-}+c.c.→J/ψπ^{+}π^{-} and determine an upper limit at the 90% confidence level for the process e^{+}e^{-}→Z_{c}(4020)^{+}π^{-}+c.c.→J/ψπ^{+}π^{-}.

Observation of Λ_{c}^{+}→nK_{S}^{0}π^{+}

We report the first direct measurement of decays of the Λ_{c}^{+} baryon involving the neutron. The analysis is performed using 567  pb^{-1} of e^{+}e^{-} collision data collected at sqrt[s]=4.599  GeV with the BESIII detector at the BEPCII collider. We observe the decay Λ_{c}^{+}→nK_{S}^{0}π^{+} and measure the absolute branching fraction to be B(Λ_{c}^{+}→nK_{S}^{0}π^{+})=[1.82±0.23(stat)±0.11(syst)]%. A comparison to B[Λ_{c}^{+}→p(K[over ¯]π)^{0}] provides an important test of isospin symmetry and final state interactions.

Precise Measurement of the e^{+}e^{-}→π^{+}π^{-}J/ψ Cross Section at Center-of-Mass Energies from 3.77 to 4.60 GeV

The cross section for the process e^{+}e^{-}→π^{+}π^{-}J/ψ is measured precisely at center-of-mass energies from 3.77 to 4.60 GeV using 9  fb^{-1} of data collected with the BESIII detector operating at the BEPCII storage ring. Two resonant structures are observed in a fit to the cross section. The first resonance has a mass of (4222.0±3.1±1.4)  MeV/c^{2} and a width of (44.1±4.3±2.0)  MeV, while the second one has a mass of (4320.0±10.4±7.0)  MeV/c^{2} and a width of (101.4_{-19.7}^{+25.3}±10.2)  MeV, where the first errors are statistical and second ones are systematic. The first resonance agrees with the Y(4260) resonance reported by previous experiments. The precision of its resonant parameters is improved significantly. The second resonance is observed in e^{+}e^{-}→π^{+}π^{-}J/ψ for the first time. The statistical significance of this resonance is estimated to be larger than 7.6σ. The mass and width of the second resonance agree with the Y(4360) resonance reported by the BABAR and Belle experiments within errors. Finally, the Y(4008) resonance previously observed by the Belle experiment is not confirmed in the description of the BESIII data.

Evidence of Two Resonant Structures in e^{+}e^{-}→π^{+}π^{-}h_{c}

The cross sections of e^{+}e^{-}→π^{+}π^{-}h_{c} at center-of-mass energies from 3.896 to 4.600 GeV are measured using data samples collected with the BESIII detector operating at the Beijing Electron Positron Collider. The cross sections are found to be of the same order of magnitude as those of e^{+}e^{-}→π^{+}π^{-}J/ψ and e^{+}e^{-}→π^{+}π^{-}ψ(2S), but the line shape is inconsistent with the Y states observed in the latter two modes. Two structures are observed in the e^{+}e^{-}→π^{+}π^{-}h_{c} cross sections around 4.22 and 4.39  GeV/c^{2}, which we call Y(4220) and Y(4390), respectively. A fit with a coherent sum of two Breit-Wigner functions results in a mass of (4218.4_{-4.5}^{+5.5}±0.9)  MeV/c^{2} and a width of (66.0_{-8.3}^{+12.3}±0.4)  MeV for the Y(4220), and a mass of (4391.5_{-6.8}^{+6.3}±1.0)  MeV/c^{2} and a width of (139.5_{-20.6}^{+16.2}±0.6)  MeV for the Y(4390), where the first uncertainties are statistical and the second ones systematic. The statistical significance of Y(4220) and Y(4390) is 10σ over one structure assumption.

Comparison of outcomes between off-pump versus on-pump coronary artery bypass surgery in elderly patients: a meta-analysis

The aim of this study was to analyze if off-pump coronary artery bypass surgery (CABG) is associated with better treatment outcomes in elderly patients (>70 years of age) than on-pump CABG, using meta-analysis. Medline, PubMed, Cochrane and Google Scholar databases were searched until September 13, 2016. Sensitivity and quality assessment were performed. Twenty-two studies, three randomized control trials (RCTs) and 20 non-RCTs were included with 24,127 patients. The risk of death associated with on-pump or off-pump CABG in the RCTs were similar (pooled OR=0.945, 95%CI=0.652 to 1.371, P=0.766). However, in the non-RCTs, mortality risk was lower in patients treated with off-pump CABG than on-pump CABG (pooled OR=0.631, 95%CI=0.587 to 0.944, P=0.003). No differences were observed between the two treatment groups in terms of the occurrence of 30-day post-operative stroke or myocardial infarction (P≥0.147). In the non-RCTs, off-pump CABG treatment was associated with a shorter length of hospital stay (pooled standardized difference in means=-0.401, 95%CI=-0.621 to -0.181, P≤0.001). The meta-analysis with pooled data from non-RCTs, but not RCTs, found that mortality was lower with off-pump compared with on-pump CABG, and suggested that there may be some benefit of off-pump CABG compared with on-pump CABG in the risk of mortality and length of hospital stay.

Amplitude Analysis of the Decays η^{'}→π^{+}π^{-}π^{0} and η^{'}→π^{0}π^{0}π^{0}

Based on a sample of 1.31×10^{9}  J/ψ events collected with the BESIII detector, an amplitude analysis of the isospin-violating decays η^{'}→π^{+}π^{-}π^{0} and η^{'}→π^{0}π^{0}π^{0} is performed. A significant P-wave contribution from η^{'}→ρ^{±}π^{∓} is observed for the first time in η^{'}→π^{+}π^{-}π^{0}. The branching fraction is determined to be B(η^{'}→ρ^{±}π^{∓})=(7.44±0.60±1.26±1.84)×10^{-4}, where the first uncertainty is statistical, the second systematic, and the third model dependent. In addition to the nonresonant S-wave component, there is a significant σ meson component. The branching fractions of the combined S-wave components are determined to be B(η^{'}→π^{+}π^{-}π^{0})_{S}=(37.63±0.77±2.22±4.48)×10^{-4} and B(η^{'}→π^{0}π^{0}π^{0})=(35.22±0.82±2.54)×10^{-4}, respectively. The latter one is consistent with previous BESIII measurements.

Measurement of Singly Cabibbo Suppressed Decays Λ_{c}^{+}→pπ^{+}π^{-} and Λ_{c}^{+}→pK^{+}K^{-}

Using 567  pb^{-1} of data collected with the BESIII detector at a center-of-mass energy of sqrt[s]=4.599  GeV, near the Λ_{c}^{+}Λ[over ¯]_{c}^{-} threshold, we study the singly Cabibbo-suppressed decays Λ_{c}^{+}→pπ^{+}π^{-} and Λ_{c}^{+}→pK^{+}K^{-}. By normalizing with respect to the Cabibbo-favored decay Λ_{c}^{+}→pK^{-}π^{+}, we obtain ratios of branching fractions: [B(Λ_{c}^{+}→pπ^{+}π^{-})/B(Λ_{c}^{+}→pK^{-}π^{+})]=(6.70±0.48±0.25)%, [B(Λ_{c}^{+}→pϕ)/B(Λ_{c}^{+}→pK^{-}π^{+})]=(1.81±0.33±0.13)%, and [B(Λ_{c}^{+}→pK^{+}K_{non-ϕ}^{-})/B(Λ_{c}^{+}→pK^{-}π^{+})]=(9.36±2.22±0.71)×10^{-3}, where the uncertainties are statistical and systematic, respectively. The absolute branching fractions are also presented. Among these measurements, the decay Λ_{c}^{+}→pπ^{+}π^{-} is observed for the first time, and the precision of the branching fraction for Λ_{c}^{+}→pK^{+}K_{non-ϕ}^{-} and Λ_{c}^{+}→pϕ is significantly improved.

[Application of 128 slice spiral CT 3D reconstruction in dorsum narrow osteotomy]

Objective:To explore the value of 128 slice spiral CT 3D reconstruction in dorsum narrow osteotomy.Method:Twenty cases of nasolacrimal duct injury patients were collected from January 2014 to June 2015 as observation group;and other 20 cases healthy adults were for control group.Maximum anteroposterior diameter and left-right diameter of lacrimal sac,distance of top and bottom of lacrimal sac,the nasolacrimal duct length,nasolacrimal duct wall thickness,nasofrontal angleand the distance of middle turbinate to the top and bottom of the lacrimal sac were analyzed by 128 slice spiral CT 3D reconstruction.Result:In the observation group,the duct length was(11.58±11.58)mm,and nasolacrimal duct wall thickness was(1.25±0.36)mm.Maximum anteroposterior diameter of lacrimal sac was(0.89±0.14)cm,and left-right diameter of lacrimal sac was(0.66±0.06)cm.The distance of top and bottom of lacrimal sac was(1.85±0.04)cm.All the parameters were statistically significant compared with the control group(P<0.05).Conclusion:The application of 128 slice spiral CT 3D reconstruction in dorsum narrow osteotomy of lacrimal duct system,not only could efficiently prevent postoperative lacrimal duct system damage,but also has important reference value in the diagnosis of postoperative lacrimal duct system damage.

Observation of an Anomalous Line Shape of the η^{'}π^{+}π^{-} Mass Spectrum near the pp[over ¯] Mass Threshold in J/ψ→γη^{'}π^{+}π^{-}

Using 1.09×10^{9} J/ψ events collected by the BESIII experiment in 2012, we study the J/ψ→γη^{'}π^{+}π^{-} process and observe a significant abrupt change in the slope of the η^{'}π^{+}π^{-} invariant mass distribution at the proton-antiproton (pp[over ¯]) mass threshold. We use two models to characterize the η^{'}π^{+}π^{-} line shape around 1.85  GeV/c^{2}: one that explicitly incorporates the opening of a decay threshold in the mass spectrum (Flatté formula), and another that is the coherent sum of two resonant amplitudes. Both fits show almost equally good agreement with data, and suggest the existence of either a broad state around 1.85  GeV/c^{2} with strong couplings to the pp[over ¯] final states or a narrow state just below the pp[over ¯] mass threshold. Although we cannot distinguish between the fits, either one supports the existence of a pp[over ¯] moleculelike state or bound state with greater than 7σ significance.

Observation of h_{c} Radiative Decay h_{c}→γη^{'} and Evidence for h_{c}→γη

A search for radiative decays of the P-wave spin singlet charmonium resonance h_{c} is performed based on 4.48×10^{8} ψ^{'} events collected with the BESIII detector operating at the BEPCII storage ring. Events of the reaction channels h_{c}→γη^{'} and γη are observed with a statistical significance of 8.4σ and 4.0σ, respectively, for the first time. The branching fractions of h_{c}→γη^{'} and h_{c}→γη are measured to be B(h_{c}→γη^{'})=(1.52±0.27±0.29)×10^{-3} and B(h_{c}→γη)=(4.7±1.5±1.4)×10^{-4}, respectively, where the first errors are statistical and the second are systematic uncertainties.

Observation of the Singly Cabibbo-Suppressed Decay D^{+}→ωπ^{+} and Evidence for D^{0}→ωπ^{0}

Based on 2.93  fb^{-1} e^{+}e^{-} collision data taken at center-of-mass energy of 3.773 GeV by the BESIII detector, we report searches for the singly Cabibbo-suppressed decays D^{+}→ωπ^{+} and D^{0}→ωπ^{0}. A double tag technique is used to measure the absolute branching fractions B(D^{+}→ωπ^{+})=(2.79±0.57±0.16)×10^{-4} and B(D^{0}→ωπ^{0})=(1.17±0.34±0.07)×10^{-4}, with statistical significances of 5.5σ and 4.1σ, where the first and second uncertainties are statistical and systematic, respectively.

Apodized waveguide arrays induced by photorefractive nonlinear surface waves

A new type of nonlinear waveguides, photorefractive surface optical waveguides is suggested, which can be induced by photorefractive surface waves on the boundary of photorefractive crystal. The disturbed refractive index distribution of such waveguides behaves as a periodic lattice with apodized envelope, thus we call them photorefractive surface apodized waveguide arrays. Moreover, the dispersion relation and corresponding modes are analyzed. It is very interesting that the dispersion curves of index-guided modes and Bragg-guided modes couple and intertwine with each other, and anti-crossings instead of crossings between them hence generate some mini-gaps. Moreover there exists a type of extraordinary modes constituted by the splice of index-guided modes and Bragg-guided modes.

Observation of a Neutral Structure near the DD[over ¯]^{*} Mass Threshold in e^{+}e^{-}→(DD[over ¯]^{*})^{0}π^{0} at sqrt[s]=4.226 and 4.257 GeV

A neutral structure in the DD[over ¯]^{*} system around the DD[over ¯]^{*} mass threshold is observed with a statistical significance greater than 10σ in the processes e^{+}e^{-}→D^{+}D^{*-}π^{0}+c.c. and e^{+}e^{-}→D^{0}D[over ¯]^{*0}π^{0}+c.c. at sqrt[s]=4.226 and 4.257 GeV in the BESIII experiment. The structure is denoted as Z_{c}(3885)^{0}. Assuming the presence of a resonance, its pole mass and width are determined to be [3885.7_{-5.7}^{+4.3}(stat)±8.4(syst)]  MeV/c^{2} and [35_{-12}^{+11}(stat)±15(syst)]  MeV, respectively. The Born cross sections are measured to be σ[e^{+}e^{-}→Z_{c}(3885)^{0}π^{0},Z_{c}(3885)^{0}→DD[over ¯]^{*}]=[77±13(stat)±17(syst)]  pb at 4.226 GeV and [47±9(stat)±10(syst)]  pb at 4.257 GeV. The ratio of decay rates B[Z_{c}(3885)^{0}→D^{+}D^{*-}+c.c.]/B[Z_{c}(3885)^{0}→D^{0}D[over ¯]^{*0}+c.c.] is determined to be 0.96±0.18(stat)±0.12(syst), consistent with no isospin violation in the process, Z_{c}(3885)^{0}→DD[over ¯]^{*}.