Observation of Y(2175) in J/psi --> etaphif0 (980)

Cortical Complexity and Connectivity during Isoflurane-induced General Anesthesia: A Rat Study

OBJECTIVE

The investigation of neurophysiologic mechanisms of anesthetic drug-induced loss of consciousness (LOC) by using the entropy, complexity, and information integration theories at the mesoscopic level has been a hot topic in recent years. However, systematic research is still lacking.

APPROACH

We analyzed electrocorticography (ECoG) data recorded from nine rats during isoflurane-induced unconsciousness. To characterize the complexity and connectivity changes, we investigated ECoG power, symbolic dynamic-based entropy (i.e., permutation entropy (PE)), complexity (i.e., permutation Lempel-Ziv complexity (PLZC)), information integration (i.e., permutation cross mutual information (PCMI)), and PCMI-based cortical brain networks in the frontal, parietal, and occipital cortical regions.

MAIN RESULTS

Firstly, LOC was accompanied by a raised power in the ECoG beta (12-30 Hz) but a decreased power in the high gamma (55-95 Hz) frequency band in all three brain regions. Secondly, PE and PLZC showed similar change trends in the lower frequency band (0.1-45 Hz), declining after LOC (p<0.05) and increasing after recovery of consciousness (p<0.001). Thirdly, intra-frontal and inter-frontal-parietal PCMI declined after LOC, in both lower (0.1-45Hz) and higher frequency bands (55-95Hz) (p<0.001). Finally, the local network parameters of the nodal clustering coefficient and nodal efficiency in the frontal region decreased after LOC, in both the lower and higher frequency bands (p<0.05). Moreover, global network parameters of the normalized average clustering coefficient and small world index increased slightly after LOC in the lower frequency band. However, this increase was not statistically significant.

SIGNIFICANCE

The PE, PLZC, PCMI and PCMI-based brain networks are effective metrics for qualifying the effects of isoflurane.

Light meson physics at BESIII

Studies of light meson decays are important tools to perform precision tests of the effective field theories, determine transition form factors and test fundamental symmetries. With very high statistics data samples, the Beijing Spectrometer III (BESIII) experiment provides a unique laboratory for light meson studies and is contributing significantly to a variety of these investigations. A brief review of recent progress in light meson decay studied at the BESIII experiment, including detailed studies of common decay dynamics, searches for rare/forbidden decays and new particles, is presented. Finally, together with descriptions of different experimental techniques, prospects for future studies of light mesons are discussed in some detail.

Observation of a Resonant Structure in e^{+}e^{-}→K^{+}K^{-}π^{0}π^{0}

A partial-wave analysis is performed for the process e^{+}e^{-}→K^{+}K^{-}π^{0}π^{0} at the center-of-mass energies ranging from 2.000 to 2.644 GeV. The data samples of e^{+}e^{-} collisions, collected by the BESIII detector at the BEPCII collider with a total integrated luminosity of 300  pb^{-1}, are analyzed. The total Born cross sections for the process e^{+}e^{-}→K^{+}K^{-}π^{0}π^{0}, as well as the Born cross sections for the subprocesses e^{+}e^{-}→ϕπ^{0}π^{0}, K^{+}(1460)K^{-}, K_{1}^{+}(1400)K^{-}, K_{1}^{+}(1270)K^{-}, and K^{*+}(892)K^{*-}(892), are measured versus the center-of-mass energy. The corresponding results for e^{+}e^{-}→K^{+}K^{-}π^{0}π^{0} and ϕπ^{0}π^{0} are consistent with those of BABAR with better precision. By analyzing the cross sections for the four subprocesses, K^{+}(1460)K^{-}, K_{1}^{+}(1400)K^{-}, K_{1}^{+}(1270)K^{-}, and K^{*+}(892)K^{*-}(892), a structure with mass M=(2126.5±16.8±12.4)  MeV/c^{2} and width Γ=(106.9±32.1±28.1)  MeV is observed with an overall statistical significance of 6.3σ, although with very limited significance in the subprocesses e^{+}e^{-}→K_{1}^{+}(1270)K^{-} and K^{*+}(892)K^{*-}(892). The resonant parameters of the observed structure suggest it can be identified with the ϕ(2170), thus the results provide valuable input to the internal nature of the ϕ(2170).

Light hadron spectroscopy at BESIII

Light hadron spectroscopy is one of the most important physics goals of high statistics of charmonium decays collected at BESIII which provide an excellent place for hunting gluonic excitations and studying strangeonium. In this proceeding, we will introduce two analyses for gluonic states study on η(1405)/η(1475) puzzle, X(1835) and exotic states and two analyses for strangeonium(like) states study on Y(2175) and Zs state.

Production of the exotic 1(--) hadrons ϕ(2170), X(4260), and Y(b)(10890) at the LHC and Tevatron via the Drell-Yan mechanism

We calculate the Drell-Yan production cross sections and differential distributions in the transverse momentum and rapidity of the J(PC) = 1(--) exotic hadrons ϕ(2170), X(4260), and Y(b)(10890) at the LHC and the Tevatron. These hadrons are tetraquark (four-quark) candidates, with a hidden ss, cc, and bb quark pair, respectively. In deriving the distributions, we include the order α(s) QCD corrections, resum the large logarithms in the small transverse momentum region in the impact-parameter formalism, and use the state of the art parton distribution functions. Production rates for the processes pp(p) → ϕ(2170)× (→ ϕ(1020)π+ π- → K+ K- π+ π-) +…, pp(p) → X(4260)(→J/ψπ+ π- → μ+ μ- π+ π-)+…, and pp(p) → Y(b)(10890)(→ Υ(1S,2S,3S)π+ π- → μ+ μ- π+ π-) +… are presented. Their measurements will help in understanding the dynamics of these exotic hadrons.

Mitotic chromosomal instability and cancer: mouse modelling of the human disease

The stepwise progression from an early dysplastic lesion to full-blown metastatic malignancy is associated with increases in genomic instability. Mitotic chromosomal instability - the inability to faithfully segregate equal chromosome complements to two daughter cells during mitosis - is a widespread phenomenon in solid tumours that is thought to serve as the fuel for tumorigenic progression. How chromosome instability (CIN) arises in tumours and what consequences it has are still, however, hotly debated issues. Here we review the recent literature with an emphasis on models that recapitulate observations from human disease.

Possibility of deeply bound hadronic molecules from single pion exchange

Pion exchange in an S wave between hadrons that are themselves in a relative S wave can shift energies by hundreds of MeV. In the case of charmed mesons D, D;{*}, D0, D1, a spectroscopy of quasimolecular states may arise consistent with enigmatic charmonium states observed above 4 GeV in e;{+}e;{-} annihilation. A possible explanation of Y(4260) --> psipipi and Y(4360) --> psi;{'}pipi is found. Searches in DD[over]3pi channels as well as B decays are recommended to test this hypothesis.