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In this work, the electron paramagnetic resonance (EPR) parameters (g-factors and A-constants) of the tetragonal VO2+ centers in LiHSO4 single crystals are theoretically investigated by the high-order perturbation formulae for these parameters based on two-spin–orbit-parameter model. Since the spin–orbit coupling coefficient of the ligand O2− is close to that of the central ion V4+ for the present system with strong covalence, the contributions to the EPR parameters from the ligand p- and s-orbitals as well as the spin–orbit coupling coefficient of the O2− ligand should be considered. The requirements of the crystal-field parameters are determined from the optical spectrum. The calculated results show good agreement with the experimental values. The signs of A-constants are ascertained in the discussion.

Graphene oxide (GO) is a kind of water soluble two-dimensional materials containing a large amount of oxygen-containing groups which infuse GO with water solubility, biocompatibility and functionality, etc. But GO can be easily reduced by losing oxygen-containing groups under some circumstances such as irradiation of $\gamma$ -ray or ultraviolet (UV). In this work, we found that acetone can significantly slow down the reduction process of GO under the irradiation of either $\gamma$ -ray or UV, which was supported by analysis results with UV-visible (UV-Vis) absorption spectra, X-ray photoelectron spectroscopy, etc. Acetone can capture and remove strongly reducible hydrated electrons generated under $\gamma$ -irradiation. GO reduction by UV also involves electron transfer process which can be affected by the presence of acetone. Hence, acetone can be used to stabilize, adjust the radiation reduction process of GO. This would be interesting not only in radiation and radiation protection, but also in understanding the redox properties of GO.

Background: Ovarian cancer is the most common cause of gynecological cancer-associated death. Iatrogenic menopause might adversely affect the quality of life and health outcomes in young female cancer survivors. We evaluated whether postoperative hormone replacement therapy (HRT) had a negative influence on the progression-free survival (PFS) of patients with papillary serous ovarian cancer (SOC). Methods: We retrospectively reviewed the medical records of patients with papillary SOC, treated from January 1980 to December 2009, who suffered from menopause with or without HRT. Clinical characteristics of patients were compared between the two groups (HRT and non-HRT). Blood samples were collected from all the participants to detect serum cancer antigen (CA) 125. Hazard ratios with 95% confidential intervals for each variable were calculated by univariable and multivariable conditional Logistic regression analyses. Results: Among 112 identified patients, 31 were HRT users and 81 were not. The two groups did not significantly differ in median age at diagnosis ( t = 0.652, P = 0.513), International Federation of Gynecology and Obstetrics (FIGO) stage ( χ 2 = 0.565, P = 0.754), differentiation ( χ 2 = 1.728, P = 0.422), resection status ( χ 2 = 0.070, P = 0.791), relapse ( χ 2 = 0.109, P = 0.741), chemotherapy course ( t = −1.079, P = 0.282), follow-up interval ( t = 0.878, P = 0.382), or PFS ( t = 0.580, P = 0.562). Median Kupperman score at the onset of HRT was 30.81 and 12.19 after the therapy ( t = 3.302, P = 0.001). According to the analysis, the strongest independent variables in predicting PFS were FIGO stage and disease that was not optimally debulked. Conclusions: Postoperative HRT is not a prognostic factor for PFS of patients with papillary SOC. However, multicenter studies are needed to verify and extend our findings.