Maternal expectations of fetal gender and risk of postpartum depression.

BACKGROUND: Female offspring was associated with a high risk of postpartum depression (PPD) during the one-child policy period in China. However, little is known about the association between maternal expectations on fetal gender and the risk of PPD in the context of the new two children policy implemented in 2016. METHODS: We conducted a hospital-based cohort study of women with singleton pregnancies between 2017 and 2018 (n = 991) to address this concern. Logistic regression was run to estimate the association between unexpected fetal gender and the risk of PPD. RESULTS: A total of 127 women (12.8%) were diagnosed with PPD. Compared with women who achieved fetal gender expectations, the odds ratio (OR) for PPD among those who had an unexpected fetal gender was 2.44 (95% confidence interval (CI): 1.30-4.58) (in the backward method logistic regression model) and 2.25 (95% CI: 1.21-4.18) (in the forward method model), respectively. The disparity of the association was significant among primiparous and pluriparous women (OR, 2.52, 95% CI: 1.32-4.84, P = 0.005 vs. OR, 0.91, 95% CI: 0.09-8.75, P = 0.932). Fetal gender expectations accounted for about 15% of the risk of PPD in the structural equation models. CONCLUSIONS: These results indicated that unexpected fetal gender was associated with an increased risk of PPD among Chinese primiparous women.

Research Progress on Triarylmethyl Radical-Based High-Efficiency OLED.

Perchlorotrityl radical (PTM), tris (2,4,6-trichlorophenyl) methyl radical (TTM), (3,5-dichloro-4-pyridyl) bis (2,4,6 trichlorophenyl) methyl radical (PyBTM), (N-carbazolyl) bis (2,4,6-trichlorophenyl) methyl radical (CzBTM), and their derivatives are stable organic radicals that exhibit light emissions at room temperature. Since these triarylmethyl radicals have an unpaired electron, their electron spins at the lowest excited state and ground state are both doublets, and the transition from the lowest excited state to the ground state does not pose the problem of a spin-forbidden reaction. When used as OLED layers, these triarylmethyl radicals exhibit unique light-emitting properties, which can increase the theoretical upper limit of the OLED's internal quantum efficiency (IQE) to 100%. In recent years, research on the luminescent properties of triarylmethyl radicals has attracted increasing attention. In this review, recent developments in these triarylmethyl radicals and their derivatives in OLED devices are introduced.