Combined effect of cortical superficial siderosis and cerebral microbleed on short-term and long-term outcomes after intracerebral haemorrhage

Background and purpose Cortical superficial siderosis(cSS)and cerebral microbleed(CMB)have distinct effects on intracerebral haemorrhage(ICH).We aim to investigate the combined effect of cSS and CMB on outcomes after ICH.Methods Based on a single-centre stroke registry database,patients with spontaneous ICH who had CT scan within 48 hours after ictus and MRI subsequently were identified.Eligible patients were divided into four groups(cSS-CMB−,cSS-CMB+,cSS+CMB−,cSS+CMB+)according to cSS and CMB on susceptibility-weighted image of MRI.Primary outcomes were haematoma volume on admission and unfavourable outcome defined as modified Rankin Scale scores≥3 at 3 months.Secondary outcomes were all-cause death,recurrence of stroke and ICH during follow-up(median follow-up 2.0 years,IQR 1.0-3.0 years).Results A total of 673 patients were identified from 1044 patients with spontaneous ICH.131(19.5%)had cSS and 468(69.5%)had CMB.Patients with cSS+CMB+had the highest rate of poor outcome at 3 months,as well as all-cause death,recurrent stroke and ICH during follow-up.In cSS−patients,CMB was associated with smaller haematoma(β−0.13;95%CI−0.22 to−0.03;p=0.009),but it still increased risks of recurrent ICH(OR 4.6;95%CI 1.3 to 15.6;p=0.015)and stroke(OR 2.0;95%CI 1.0 to 4.0;p=0.049).These effects of CMB became unremarkable in the context of cSS+.Conclusions Patients with different combinations of cSS and CMB have distinct patterns of short-term and long-term outcomes.Although CMB is related to restrained haematoma,it does not improve long-term outcomes.

Study of the XYZ states at the BESIII

With its unique data samples at energies of 3.8-4.6 GeV, the BESIII experiment made a significant contribution to the study of charmonium and charinonium-like states, i.e., the XYZ states. We review the results for observations of the Zc（3900） and Zc（4020） states, the X（3872） in e^＋e^- annihilation, and charmonium ψ（13D2） state, as well as measurements of the cross-sections of ωχcJ and ηJ/ψ, and the search for e^＋e^-→γχcJ and γY（4140）. We also present data from BESIII that may further strengthen the study of the XYZ and conventional charmonium states, and discuss perspectives on future experiments.

Observation of pentaquark states and prospectives of further studies

The quark model based on quark–antiquark mesons and three-quark baryons has been very successful in classifying the hadrons.However,quantum chromodynamics(QCD)does not forbid the existence of exotic hadronic states with other quark–gluon configurations,such as

Sensitivity study of searching for τ^-→γμ^- at HIEPA

The charged lepton flavor violation process is a clean and sensitive probe of new physics beyond the Standard Model. A sensitivity study is performed to the process τ^-→γμ^- based on a 3 fb^(-1) inclusive Monte Carlo sample of e^+e^- collisions at a center-of-mass energy of4.26 or 4.6 Ge V, in the framework of the BESIII software system. The 90 % confidence level upper limits on B(τ^-→γμ^-) are estimated assuming no signal is produced. We also obtain the sensitivity on B(τ^-→γμ^-) as a function of the integrated luminosity, to serve as a reference for the HIEPA being proposed in China. It is found that 6.34 ab^(-1) are needed to reach the current best upper limit of 4:4 10^(-8) and about 2510 ab^(-1) are needed to reach a sensitivity of 10^(-9) if the detector design is similar to that of BESIII.

Suppression of top-up injection backgrounds with offline event filter in the BESIII experiment

Background It is imperative that high-quality data should be accumulated to guarantee the correctness and accuracy of physics results in particle physics experiments.The top-up injection of BEPCII has achieved a definite improvement in integrated luminosity,but simultaneously has an obvious impact on the background level of the data acquired by the BESIII detector due to frequent beam injections.Methods An online trigger veto and an offline eventfilter have been developed and applied to eliminate the contaminated events from the data samples for physics research.Results and Conclusion The design and implementation of offline eventfilter are described in this article.The upgraded offline data processing procedure with offline eventfilter was executed smoothly in recent years and ensured data acquisition and processing with optimal efficiency and sufficient quality in BESIII experiment.

New puzzle in charmonium decays

By analyzing existing data on pseudoscalar charmonium decays,we obtain the ratio of the branching fractions of η_(c)(2S) and η_(c) decays into ten different final states with light hadrons.For the first time,we test the two existing theoretical predictions of these decays and find that the experimental data are significantly different from both of them.The lack of observation of any decay mode with higher rate in η_(c)(2S)than in η_(c) decays suggests very unusual decay dynamics in pseudoscalar charmonium decays to be identified.We also report the first model-independent evaluation of the partial width of η_(c)(2S)→yy(2.21^(+0.88)_(-0.64)keV)and improve determination of that of η_(c)→yy(5.43^(+0.41)_(-0.38)KeV).The latter shows a tension with the most recent lattice QCD calculation.

Hadronic cross section of e^+e^- annihilation at bottomonium energy region

The Born cross section and dressed cross section of e+e−→bb¯and the total hadronic cross section in e+e−annihilation in the bottomonium energy region are calculated based on the Rb values measured by the BaBar and Belle experiments.The data are used to calculate the vacuum polarization factors in the bottomonium energy region,and to determine the resonant parameters of the vector bottomonium(-like)states Y(10750),Υ(5S),andΥ(6S).

Derived Born cross sections of e^+e^-annihilation into open charm mesons from CLEO-c measurements

The exclusive Born cross sections of the production of D0, D＋ and Ds＋ mesons in e＋e- annihilation at 13 energy points between 3.970 and 4.260 GeV are obtained by applying corrections for initial state radiation and vacuum polarization to the observed cross sections measured by the CLEO-c experiment. Both the statistical and the systematic uncertainties for the obtained Born cross sections are estimated.