Theoretical analysis of direct CPCP violation and differential decay width in D±→π±π+π−D^\pm\to \pi^\pm \pi^+\pi^- in phase space around the resonances ρ0(770)\rho^0(770) and f0(500)f_0(500)

We perform a theoretical study on direct $CP$ violation in $D^\pm\to \pi^\pm \pi^+\pi^-$ in phase space around the intermediate states $\rho^0(770)$ and $f_0(500)$. The possible interference between the amplitudes corresponding to the two resonances is taken into account, and the relative strong phase of the two amplitudes is treated as a free parameter. Our analysis shows that by properly chosen the strong phase, both the $CP$ violation strength and differential decay width accommodate to the experimental results.Comment: 15 pages, 5 figure

Electroweak radiative corrections to triple photon production at the ILC

In this paper, we present the precision predictions for three photon production in the standard model (SM) at the ILC including the full next-to-leading (NLO) electroweak (EW) corrections, high order initial state radiation (h.o.ISR) contributions and beamstrahlung effects. We present the LO and the NLO EW+h.o.ISR+beamstrahlung corrected total cross sections for various colliding energy when $\sqrt s \ge 200 {\rm GeV}$ and the kinematic distributions of final photons with $\sqrt s = 500 {\rm GeV}$ at ILC, and find that the NLO EW corrections, the h.o.ISR contributions and the beamstrahlung effects are important in exploring the process $e^+e^- \to \gamma\gamma\gamma$.Comment: 6 pages, 8 figures, accepted for publication in Physics Letters

Production of charged ρ\rho meson in bottom hadron charmed decays and the effect of the finite width correction of the ρ\rho meson

We calculate the branching ratio of a bottom hadron decaying into a charmed hadron and a charged $\rho$ meson within the QCD factorization approach. We consider the effect of the finite width correction of the $\rho$ meson. Our numerical calculation shows an obvious correction because of this effect. We find that the finite width effect of the $\rho$ meson reduces the branching ratios by about 9% to 11% for bottom meson decay channels: $B^+\to\bar{D^0}\rho^+$, $B^0\to D^-\rho^+$, and $B^0_s\to D^-_s\rho^+$, and increases the branching ratio by about 10% for $\Lambda_b^0\to\Lambda_c^+\rho^-$.Comment: 12 page

Investigation of the potential role of checkpoint kinase2 in the regulation of gastric cancer stem cells

Purpose: To investigate the potential role of checkpoint kinase2 (CHEK2) in regulating gastric cancer stem cells.Methods: The abnormal features of cellular arrangements in early and advanced stages of gastric cancer were analysed using histology. Immunohistochemistry and Western blotting were used to evaluate the expressions of cancer stem cell markers CD44 and CHEK2 at different stages of gastric cancer.Results: When compared with the control tissue, the size of the cellular nucleus was enlarged as the gastric tumour developed to more advanced stages, and the expression of CD44 increased exponentially. The expression of CHEK2, a protein that regulates cell cycle and apoptosis was aberrantly up-regulated at the early stage of cancer, but as the tumour advanced, its expression became down-regulated.Conclusion: These results show that the higher expression of CHEK2 at the early stages of gastric cancer exerts control over gastric cancer stem cell proliferation. Thus, CHECK2 is a potential target for early treatment of gastric cancer.Keywords: Gastric cancer, CD44, CHEK2, Gastric cancer stem cell

Twist-3 light-cone distribution amplitudes of the scalar mesons within the QCD sum rules and their application to the B→SB \to S transition form factors

We investigate the twist-3 light-cone distribution amplitudes (LCDAs) of the scalar mesons $a_0$, $K^{\ast}_0$ and $f_0$ within the QCD sum rules. The QCD sum rules are improved by a consistent treatment of the sizable $s$-quark mass effects within the framework of the background field approach. Adopting the valence quark component $(\bar{q}_1 q_2)$ as the dominant structure of the scalar mesons, our estimation for their masses are close to the measured $a_0(1450)$, $K^{\ast}_0(1430)$ and $f_0(1710)$. From the sum rules, we obtain the first two non-zero moments of the twist-3 LCDAs $\phi^{s,\sigma}_{a_0}$: $\langle \xi_{s,a_0}^{2(4)} \rangle=0.369 \;(0.245)$ and $\langle \xi_{\sigma,a_0}^{2(4)} \rangle=0.203 \;(0.093)$; those of the twist-3 LCDAs $\phi_{K^*_0}^{s,\sigma}$: $\langle \xi_{s,K^{\ast}_0}^{1(2)} \rangle =0.004\;(0.355)$ and $\langle \xi_{\sigma,K^{\ast}_0}^{1(2)} \rangle =0.018\;(0.207)$; and those of the twist-3 LCDAs $\phi_{f_0}^{s,\sigma}$: $\langle \xi_{s,f_0}^{2(4)} \rangle=0.335 \;(0.212)$ and $\langle \xi_{\sigma,f_0}^{2(4)} \rangle=0.196 \; (0.088)$, respectively. As an application of those twist-3 LCDAs, we study the $B \to S$ transition form factors by introducing proper chiral currents into the correlator, which is constructed such that the twist-3 LCDAs give dominant contribution and the twist-2 LCDAs make negligible contribution. Our results of the $B \to S$ transition form factors at the large recoil region $q^2 \simeq 0$ are consistent with those obtained in the literature, which inversely shows the present twist-3 LCDAs are acceptable.Comment: 14 pages, 12 figures, 7 table