Proton-Antiproton Annihilation in Baryonium

A possible interpretation of the near-threshold enhancement in the $(p\bar{p})$-mass spectrum in $J/\psi{\to}\gamma p{\bar p}$ is the of existence of a narrow baryonium resonance X(1860). Mesonic decays of the $(p\bar{p})$-bound state X(1860) due to the nucleon-antinucleon annihilation are investigated in this paper. Mesonic coherent states with fixed $G$-parity and $P$-parity have been constructed . The Amado-Cannata-Dedoder-Locher-Shao formulation(Phys Rev Lett. {\bf 72}, 970 (1994)) is extended to the decays of the X(1860). By this method, the branch-fraction ratios of $Br(X\to \eta 4\pi)$, $Br(X\to \eta 2\pi)$ and $Br(X\to 3\eta)$ are calculated. It is shown that if the X(1860) is a bound state of $(p\bar{p})$, the decay channel ($X\to \eta 4\pi)$ is favored over $(X\to \eta 2\pi)$. In this way, we develop criteria for distinguishing the baryonium interpretation for the near-threshold enhancement effects in $(p\bar{p})$-mass spectrum in $J/\psi{\to}\gamma p{\bar p}$ from other possibilities. Experimental checks are expected. An intuitive picture for our results is discussed.Comment: 19 pages, 3 figure

Quantum Anomalous Hall Effect in Hg1−y_{1-y}Mny_{y}Te Quantum Wells

The quantum Hall effect is usually observed when the two-dimensional electron gas is subjected to an external magnetic field, so that their quantum states form Landau levels. In this work we predict that a new phenomenon, the quantum anomalous Hall effect, can be realized in Hg$_{1-y}$Mn$_{y}$Te quantum wells, without the external magnetic field and the associated Landau levels. This effect arises purely from the spin polarization of the $Mn$ atoms, and the quantized Hall conductance is predicted for a range of quantum well thickness and the concentration of the $Mn$ atoms. This effect enables dissipationless charge current in spintronics devices.Comment: 5 pages, 3 figures. For high resolution figures see final published version when availabl

Endoscopic Removal of an Impacted Needle with Syringe from the Esophagus

AbstractBackgroundIn adults, non-food foreign body ingestions occur more in denture users, incarcerated individuals, and in patients with psychiatric disorders or alcohol intoxication. The majority of the ingested foreign body will pass spontaneously. Sharp or pointed foreign body, animal or fish bones, and magnets increase the risk of perforation.PatientAn incarcerated patient with bipolar disorder swallowed a 14cm in length needle attached with a syringe three months prior to presentation. The needle penetrated the distal esophagus leading to mediastinitis.MethodsIn this video manuscript, we demonstrated endoscopic techniques on how to remove this 14cm long sharp object.ResultsThe foreign body was removed uneventfully and mediastinitis resolved with antibiotic treatment.ConclusionsEmergent endoscopy is indicated in (1) esophageal obstruction and the patient are unable to swallow secretions and (2) disk batteries and sharp-pointed foreign body in the esophagus

Effect of allicin on THP-1, MT-2 and WISH cell apoptosis induced by vesicular stomatitis virus (VSV) and the molecular mechanism involved

Vesicular stomatitis virus (VSV) has been reported to induce apoptosis and the onset of apoptosis may play an important role in virus-associated diseases. This study was conducted in order to investigate the protective effect of the herbal constituent allicin on VSV-induced apoptosis in the human monocyte line THP-1, human T lymphocytic leukemia cell line MT-2 and human amniotic cell line WISH and to determine the possible molecular mechanism involved. The THP-1, MT-2 and WISH cells were incubated with VSV in the absence or presence of different doses of allicin (10, 25 and 50 μg/ml). To study apoptosis, the cells were assessed by MTT and annexin V-propidium iodide double-staining flow cytometry. To investigate the molecular mechanism by which allicin regulates VSV-induced THP-1, MT-2 and WISH cell apoptosis, the expression of active cleavage products of caspases 3, 6, 7 and 9 and NF-κB was analyzed by western blotting. Our results indicated that allicin did not affect the adhesion and entry of VSV into THP-1, MT-2 or WISH cells. Using different concentrations of allicin, a dose-dependent protective effect on  cell apoptosis was observed. In addition, the VSV-induced expression of active cleavage products of caspases 3, 6, 7 and 9 and NF-κB in THP-1, MT-2 and WISH cells was also significantly reduced by allicin at the protein level. We concluded that allicin protects THP-1, MT-2 and WISH cells from VSV-induced apoptosis by inhibiting the activation of caspases 3, 6, 7 and 9 and NF-κB, thereby suggesting a potential protective effect for allicin against virus-associated diseases.Key words: Allicin, vesicular stomatitis virus (VSV), apoptosis, caspases, NF-κB

Multi-Receiver Quantum Dense Coding with Non-Symmetric Quantum Channel

A two-receiver quantum dense coding scheme and an $N$-receiver quantum dense coding scheme, in the case of non-symmetric Hilbert spaces of the particles of the quantum channel, are investigated in this paper. A sender can send his messages to many receivers simultaneously. The scheme can be applied to quantum secret sharing and controlled quantum dense coding.Comment: To appear in Journal of the Korean Physical Societ

Exclusive B→VVB \to VV Decays and CP Violation in the General two-Higgs-doublet Model

Using the general factorization approach, we present a detailed investigation for the branching ratios, CP asymmetries and longitudinal polarization fractions in all charmless hadronic $B \to VV$ decays (except for the pure annihilation processes) within the most general two-Higgs-doublet model with spontaneous CP violation. It is seen that such a new physics model only has very small contributions to the branching ratios and longitudinal polarization fractions. However, as the model has rich CP-violating sources, it can lead to significant effects on the CP asymmetries, especially on those of penguin-dominated decay modes, which provides good signals for probing new physics beyond the SM in the future B-physics experiments.Comment: 17 pages, no figure

Dynamical Axion Field in Topological Magnetic Insulators

Axions are very light, very weakly interacting particles postulated more than 30 years ago in the context of the Standard Model of particle physics. Their existence could explain the missing dark matter of the universe. However, despite intensive searches, they have yet to be detected. In this work, we show that magnetic fluctuations of topological insulators couple to the electromagnetic fields exactly like the axions, and propose several experiments to detect this dynamical axion field. In particular, we show that the axion coupling enables a nonlinear modulation of the electromagnetic field, leading to attenuated total reflection. We propose a novel optical modulators device based on this principle.Comment: 5 pages, 3 figure

A new approach to bulk viscosity in strange quark matter at high densities

A new method is proposed to compute the bulk viscosity in strange quark matter at high densities. Using the method it is straightforward to prove that the bulk viscosity is positive definite, which is not so easy to accomplish in other approaches especially for multi-component fluids like strange quark matter with light up and down quarks and massive strange quarks.Comment: 7pages, talk given in SQM2008. Minor revisions, including clarification and updated reference