Protective effect of Rhizoma drynariae extract on osteoporosis in ovariectomized rat model

Purpose: To investigate the therapeutic effect of Rhizoma Drynariae extract (RDE) on ovariectomyinduced osteoporosis in rats.Methods: Female Sprague-Dawley rats were randomly assigned to a sham-operated group (control) and five ovariectomy (OVX) subgroups: OVX with vehicle (OVX), OVX with 17ß-estradiol (E2, 25 μg/kg/day), and OVX with RDE doses (40, 80, and 160 mg/kg/day). Daily oral administration of E2 or RDE started 4 weeks after OVX and lasted for 16 weeks. The bone mineral density (BMD) of the L4 vertebrae and right femurs was estimated. The length of each femur was measured with a  micrometer gauge, and the center of the diaphysis determined. Three   representatives L4 vertebrae were selected to evaluate the trabecular  microarchitecture. Serum alkaline phosphatase (ALP), urinary calcium (U-Ca),urinary phosphorus (U-P), urinary creatinine (Cr) and osteocalcin (OC) levels were measured.Results: The study showed that high-dose of RDE significantly inhibited the bone mineral density (BMD) reduction of L4 vertebrae (0.20 ± 0.02 g/cm3, p < 0.05) and femurs (0.18 ± 0.02 g/cm3, p < 0.05) caused by OVX and prevented the  deterioration of trabecular microarchitecture (p < 0.05), which were accompanied by a significant decrease in skeletal remodeling (p < 0.05) as evidenced by the lowerlevels of bone turnover markers. High-dose of RDE improved morphometric parameters, namely, Tb-N (3.8 ± 0.2 mm, p < 0.05), Tb-Th (0.083 ± 0.011 mm, p < 0.05) and Tb-Sp (0.19 ± 0.01 mm, p < 0.05) in L4 vertebrae significantly. The present study indicates that the administration of RDE at higher doses over a  16-week period can prevent OVX-induced osteoporosis in rats without hyperplastic effects on the uterus.Conclusion: Thus, RDE is a potential natural alternative for postmenopausal  osteoporosis treatment in elderly women.Keywords: Rhizoma Drynariae, Postmenopausal osteoporosis, Ovariectomy, Bone mineral density, Morphometri

Implications on the first observation of charm CPV at LHCb

Very recently, the LHCb Collaboration observed the $CP$ violation (CPV) in the charm sector for the first time, with $\Delta A_{CP}^{\rm dir}\equiv A_{CP}(D^0\to K^+K^-)-A_{CP}(D^0\to \pi^+\pi^-)=(-1.54\pm0.29)\times10^{-3}$. This result is consistent with our prediction of $\Delta A_{CP}^{\rm SM}=(-0.57\sim -1.87)\times 10^{-3}$ obtained in the factorization-assisted topological-amplitude (FAT) approach in [PRD86,036012(2012)]. It implies that the current understanding of the penguin dynamics in charm decays in the Standard Model is reasonable. Motivated by the success of the FAT approach, we further suggest to measure the $D^+\to K^+K^-\pi^+$ decay, which is the next potential mode to reveal the CPV of the same order as $10^{-3}$.Comment: 10 page

Phase transitions in a holographic s+p model with backreaction

In a previous paper (arXiv:1309.2204, JHEP 1311 (2013) 087), we present a holographic s+p superconductor model with a scalar triplet charged under an SU(2) gauge field in the bulk. We also study the competition and coexistence of the s-wave and p-wave orders in the probe limit. In this work we continue to study the model by considering the full back-reaction The model shows a rich phase structure and various condensate behaviors such as the "n-type" and "u-type" ones, which are also known as reentrant phase transitions in condensed matter physics. The phase transitions to the p-wave phase or s+p coexisting phase become first order in strong back-reaction cases. In these first order phase transitions, the free energy curve always forms a swallow tail shape, in which the unstable s+p solution can also play an important role. The phase diagrams of this model are given in terms of the dimension of the scalar order and the temperature in the cases of eight different values of the back reaction parameter, which show that the region for the s+p coexisting phase is enlarged with a small or medium back reaction parameter, but is reduced in the strong back-reaction cases.Comment: 15 pages(two-column), 9 figure