A Simple Three-Parameter Model Potential For Diatomic Systems: From Weakly and Strongly Bound Molecules to Metastable Molecular Ions

Based on a simplest molecular orbital theory of H$_{2}^{+}$, a three-parameter model potential function is proposed to describe ground-state diatomic systems with closed-shell and/or S-type valence-shell constituents over a significantly wide range of internuclear distances. More than 200 weakly and strongly bound diatomics have been studied, including neutral and singly-charged diatomics (e.g., H$_{2}$, Li$_{2}$, LiH, Cd$_{2}$, Na$_{2}^{+}$, and RbH$^{-}$), long-range bound diatomics (e.g., NaAr, CdNe, He$_{2}$, CaHe, SrHe, and BaHe), metastable molecular dications (e.g., BeH$^{++}$, AlH$^{++}$, Mg$_{2}^{++}$, and LiBa$^{++}$), and molecular trications (e.g., YHe$^{+++}$ and ScHe$^{+++}$).Comment: 5 pages, 4 figures, accepted by Physical Review Letter

Theoretical analysis of dynamic chemical imaging with lasers using high-order harmonic generation

We report theoretical investigations of the tomographic procedure suggested by Itatani {\it et al.} [Nature, {\bf 432} 867 (2004)] for reconstructing highest occupied molecular orbitals (HOMO) using high-order harmonic generation (HHG). Using the limited range of harmonics from the plateau region, we found that under the most favorable assumptions, it is still very difficult to obtain accurate HOMO wavefunction, but the symmetry of the HOMO and the internuclear separation between the atoms can be accurately extracted, especially when lasers of longer wavelengths are used to generate the HHG. We also considered the possible removal or relaxation of the approximations used in the tomographic method in actual applications. We suggest that for chemical imaging, in the future it is better to use an iterative method to locate the positions of atoms in the molecule such that the resulting HHG best fits the macroscopic HHG data, rather than by the tomographic method.Comment: 13 pages, 14 figure

Generation of higher-order atomic dipole squeezing in a high-Q micromaser cavity: VIII. multi-photon interaction

In our preceding serial works, we have investigated the generation of higher-order atomic dipole squeezing (HOADS) in a high-Q micromaser cavity, discussing the effects of dynamic Stark shift, atomic damping, atomic coherence and nonlinear one-photon processes and different initial states (for example, correlated and uncorrelated states, superposition states, squeezed vacuum). In this paper, we continue to study HOADS in a high-Q micromaser cavity, but consider that the atom interacts with the optical field via a multi-photon transition process and that the initial atom is arbitrarily prepared. For a vacuum initial field, we demonstrate that HOADS cannot occur if the atom is initially prepared in a chaotic state and that a coherent atomic state generates less efficient and stable HOADS than an arbitrary one. It is found that large detuning may lead to enhanced and strong HOADS.Comment: 8 figure

Dydrogesterone has no effect on uterine fibroids when used to prevent miscarriage in pregnant women with uterine fibroids

Objectives: To analyse the effect of dydrogesterone use during pregnancy on uterine fibroids, pregnancy complications, and pregnancy outcome. Material and methods: In all, 372 pregnant women with uterine fibroids who were treated at the Affiliated Provincial Hospital of Shandong University were included in this study. Thirty-three of these women received dydrogesterone and constituted the treatment group, and the 27 women who were found to have uterine fibroids during the first trimester but did not receive intervention to prevent miscarriage composed the control group. The changes in uterine fibroids before and after pregnancy and the pregnancy complications were recorded; immunohistochemistry was used to detect the expression of progesterone receptor (PR) and proliferation- and apoptosis-related proteins in the uterine fibroid tissue. Results: No significant difference was observed in the change in uterine fibroid volume during pregnancy between the treatment group and the control group (p > 0.05). The percentage of uterine fibroids with red degeneration was lower in the treatment group than in the control group, but the difference was not statistically significant. No significant difference was observed in newborn weight, height, Apgar score, threatened miscarriage, or premature birth, among other characteristics, between the two groups (p > 0.05). Immunohistochemistry showed no significant difference in the expression of PR, cyclinD1, insulin-like growth factor (IGF1), or B-cell lymphoma 2 (Bcl2) between the two groups. Conclusions: The use of dydrogesterone during pregnancy has no significant effect on uterine fibroids, pregnancy progression, or pregnancy outcomes in pregnant patients with uterine fibroids