Isospin violation in ϕ,J/ψ,ψ′→ωπ0\phi, J/\psi, \psi^\prime \to \omega \pi^0 via hadronic loops

In this work, we study the isospin-violating decay of $\phi\to \omega\pi^0$ and quantify the electromagnetic (EM) transitions and intermediate meson exchanges as two major sources of the decay mechanisms. In the EM decays, the present datum status allows a good constraint on the EM decay form factor in the vector meson dominance (VMD) model, and it turns out that the EM transition can only account for about $1/4\sim 1/3$ of the branching ratio for $\phi\to \omega\pi^0$. The intermediate meson exchanges, $K\bar{K}(K^*)$ (intermediate $K\bar{K}$ interaction via $K^*$ exchanges), $K\bar{K^*}(K)$ (intermediate $K\bar{K^*}$ rescattering via kaon exchanges), and $K\bar{K^*}(K^*)$ (intermediate $K\bar{K^*}$ rescattering via $K^*$ exchanges), which evade the naive Okubo-Zweig-Iizuka (OZI) rule, serve as another important contribution to the isospin violations. They are evaluated with effective Lagrangians where explicit constraints from experiment can be applied. Combining these three contributions, we obtain results in good agreement with the experimental data. This approach is also extended to $J/\psi(\psi^\prime)\to \omega\pi^0$, where we find contributions from the $K\bar{K}(K^*)$, $K\bar{K^*}(K)$ and $K\bar{K^*}(K^*)$ loops are negligibly small, and the isospin violation is likely to be dominated by the EM transition.Comment: Revised version resubmitted to PRD; Additional loop contributions included; Conclusion unchange

Intersite Coulomb repulsion driven quadrupole instability and magnetic ordering in the orbital frustrated Ba2_2MgReO6_6

We develop an unrestricted Hartree-Fock mean-field method including Coulomb repulsion U, V and spin-orbital coupling $\lambda$ self$-$consistently to investigate the mechanism of structural instability and magnetic ordering in Ba$_2$MgReO$_6$. A comprehensive quadrupole phase diagram versus U and V with $\lambda$=0.28eV is calculated. Our results demonstrate that, while U and $\lambda$ mainly lead to the onsite quadrupole $Q_{x^2-y^2}$ and $Q_{3z^2-r^2}$ with orbital frustration, the easy-plane anisotropy or the intersite Coulomb repulsion V can remove the frustration. Finally, the V$>$10meV would arrange $Q_{x^2-y^2}$ antiparallelly, accompanied with small parallel $Q_{3z^2-r^2}$, and stabilize Ba$_2$MgReO$_6$ into the body centered tetragonal structure. Such antiparallel $Q_{x^2-y^2}$ provides a new mechanism of Dzyaloshinskii-Moriya interaction, and gives rise to the canted antiferromagnetic (CAF) state along [110] axis. Moreover, sizable octupoles such as $O_{21}^{31}$, $O_{21}^{33}$, $O_{21}^{34}$ and $O_{21}^{36}$ are discovered for the first time in CAF states. Our study not only provides a comprehensive understanding of the nature and exotic properties in Ba$_2$MgReO$_6$, but also reveals some commonality of 5d compounds

Controlled Levofloxacin Release and Antibacterial Properties of β-Cyclodextrins-Grafted Polypropylene Mesh Devices for Hernia Repair.

Mesh infection is a major complication of hernia repair. After knitted mesh implantation, bacteria can grow within textile structures causing infection. In this work, polypropylene (PP) mesh devices were two-step grafted with hexamethylene diisocyanate (HDI) and β⁻cyclodexrins (CD) and then loaded with suitable antimicrobial levofloxacin HCL for hernia mesh-infection prevention. First, oxygen plasma was able to create surface roughness, then HDI was successfully grafted onto PP fiber surfaces. Afterwards, CD was covalently grafted onto the HDI treated PP meshes, and levofloxacin HCL (LVFX) was loaded into the CD cavity of the modified meshes. The modified devices were evaluated for sustained antibiotic properties and drug-release profiles in a phosphate buffer, and sustained drug release was observed between interfaces of meshes and aqueous environment. The antibiotic-loaded PP mesh samples demonstrated sustained antibacterial properties for 7 and 10 days, respectively, against both Gram-negative and Gram-positive bacteria. The CD-captured levofloxacin HCL showed burst release after 6 h but later exhibited sustained release for the next 48 h. Among all samples, the modified mesh LVFX-6 was more stable and showed more sustained drug release and could be employed in future clinical applications