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As the cardinal part of capacitive deionization apparatus, the performance of electrode directly determines the capacitive deionization's adsorption rate, adsorption capacity and selectivity. However, the adsorptivity and reusability of electrode material for special adsorbate need to be developed urgently for the application of capacitive deionization in wastewater purification. In this research, we successfully enhanced the Cu(II) adsorptivity of activated carbon fiber felt (ACFF) to 23 mg/g (4.47 times of ACFF0) by the sonication‐assisted chemical reactivation process with the solution of 20 wt % NaOH used as activator (ACFF‐N20). As ACFF‐N20 used as cathode, the Cu(II) electro‐adsorptivity of ACFF‐N20 under a current of 0.15 A is 84 mg/g for 130 mg/L Cu(II) standard working fluid. For the Cu(II) wastewater with a concentration of 50 mg/L, it can be purified to 0.14 mg/L by one step of capacitive deionization, which below the drinking standard of World Health Organization. By the technology of low‐temperature pickling regeneration, the regeneration rates of ACFF‐N20 are 102 %–106 % for five recycling times of Cu(II) electrosorption process. Based on fitting analysis of adsorption processes using different kinetic models, it was found that Langmuir model is more convergent than Freundlich model to the adsorption isotherms. Additionally, Bangham adsorption kinetic model and pseudo‐first order adsorption kinetic model have the best fitting correlation for the Cu(II) static adsorption and electrosorption of ACFFs. [ABSTRACT FROM AUTHOR]

Objective: To compare the maternal and neonatal outcomes of twin pregnancies between vertex and nonvertex presentations of the second twin in vaginal delivery. Methods: In this unicentric retrospective cohort study, we collected data from 213 cases of vaginal twin deliveries from January 2016 to July 2020. Participants were divided into the vertex‐vertex presentation group (VV) and vertex‐breech presentation group (VB). Data on maternal and neonatal outcomes were compared between groups. Results: Among the 213 mothers and 426 infants (213 twin pairs), there were 140 women in the VV group and 73 women in the VB group (65.73% vs. 34.27%). Infants in the VB group had a higher incidence of admission to NICU (51.43% vs. 68.49%, p = 0.017), lower 1‐min (11.43% vs. 28.77%, p < 0.001) and 5‐minute Apgar scores (1.43% vs. 4.11%, p = 0.043) for the second twin. However, after the adjustment for sex of the twin, birth weight, chorionicity, and gestational age, the greater risk of admission to NICU and low 5‐min Apgar score was no longer significantly different. Conclusion: VB twins are at no greater overall risk of a poor outcome due to breech presentation in the second twin. However, the presentation of the second fetus represents a risk factor for a low 1‐min Apgar score. Obstetricians and midwives should consider appropriate interventions for second twins who present breech versus vertex. [ABSTRACT FROM AUTHOR]

The N‐(4‐hydroxyphenyl) maleimide (4‐HPM) modified waterborne polyurethane emulsions (MWPU) were used as surface sizing agents to improve the interfacial adhesion between carbon fibers (CF) and epoxy resin matrix. Dynamic light scattering (DLS), transmission electron microscope (TEM), and thermogravimetric analysis (TGA) showed the particle size distribution, storage stability, and thermal stability of the modified MWPU. And the surface reactivity of CF increased significantly after sizing. The interfacial shear strength (IFSS) and the interlaminar shear strength (ILSS) of CFREs were tested, and the fracture morphology was observed. The result showed that a continuous and uniform sizing layer is formed on the surface of CF. In particular, the comprehensive performance and interfacial modification effect of the MWPU emulsion outperformed other samples when the 4‐HPM content was 1.0 wt%. Compared with unsized carbon fibers, the IFSS and ILSS are up to 71.30% and 30.81% higher, respectively. [ABSTRACT FROM AUTHOR]

Aim: Unpredictable nature of infant sleep–wake cycles go against that of the adult sleep. Maternal sleep quality is acknowledged as a main factor to postpartum fatigue. This study explored the effects of infant sleep patterns on maternal postpartum fatigue. Methods: A total of 319 mothers of infants from two teaching hospitals in the Nantong City were enrolled. Maternal fatigue status and infant sleep patterns were assessed by the Fatigue Scale (FS‐14) and the Brief Infant Sleep Questionnaire (BISQ). Generalized estimating equation analyses were perform to explored the effect of infant sleep patterns on maternal fatigue. Results: Sleep‐onset time later than 10 p.m., and nocturnal wakefulness more than 60 min were risk factors of postpartum fatigue. After controlling the confounding variables, infant sleep patterns were still the determinant factors of postpartum fatigue. Conclusion: Infant sleep pattern is a factor of maternal postpartum fatigue. It is recommended to promote infant sleep so as to improve maternal sleep quality and finally alleviate postpartum fatigue. [ABSTRACT FROM AUTHOR]