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.

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%.

[Probing R6G single molecules by surface-enhanced resonance Raman scattering].

R6G was incubated in three kinds of silver colloid with different low concentrations, and its surface-enhanced resonance Raman scattering (SERRS) was studied with a confocal microscopy system. Each sample exhibited different spectrum character. At the single-molecule level the SERRS-spectra were recorded in 10(-13) mol x L(-1) dye colloidal solution.