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In order to enhance the interfacial bonding between carbon fibers (CFs) and the polypropylene (PP) resin matrix, the modified acrylate nanoemulsion was prepared by emulsifying modified chlorinated polypropylene (CPP) by phase conversion. The nanoemulsion is safer and environmentally friendly than commercial solvent-based nanoemulsions. The nanoemulsion possesses good stability owing to its regular droplet shape and uniform distribution (droplet size <100 nm, absolute zeta potential >40 mV) and is highly suitable for PP resins. The surface properties of CFs, including chemical composition, morphology, wettability, and interfacial adhesion were systematically investigated. Compared to unsized CFs, the surface roughness of sized CFs was reduced and the surface wettability was improved due to the increased surface oxygen content. As the nanoemulsion was uniformly coated on the CFs, the tensile strength and the interlaminar shear strength (ILSS) of the composite were both enhanced. Specifically, the ILSS of the composite sized with the P3 nanoemulsion has increased by 48.5%, indicating that the composite's mechanical strength and interfacial bonding significantly improved due to the nanoemulsion. On this basis, a dual physical and chemical interfacial strength mechanism of the nanoemulsion in the composite was proposed, and an effective and feasible method was proposed to solve the weak interfacial bonding between CFs and PP. [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]

Aim: To explore the correlation between pregnant fatigue and intrauterine physical and neural development of offspring in rats. Methods: Sprague-Dawley pregnant rats were randomly divided into a normal control group, a mild fatigue group (stand in water for 6 hours/day), and a severe fatigue group (stand in water for 15 h/day). The levels of lactic acid, 5-Hydroxytryptamine and Interleukin-6 in cardiac serum of rats were used to evaluate the fatigue. The expression of S100β in the telencephalon, Insulin-like growth factor-1 (IGF-1) in the liver and Cyclooxygenage-2 (COX-2) in the small intestine tissues of fetal rats were examined. Frozen sections were taken from the telencephalon of rat pups to observe morphological changes in the hippocampal primordium. Results: Pregnant fatigue led to a decrease in food intake (F = 37.586, p = 0.000) and water intake (F = 23.608, p = 0.000) in rats. The IGF-1 mRNA expression of fetal rats in the severe fatigue group was lower than that in the control group (p = 0.0003). The expression of S100β mRNA (p = 0.000) and COX-2 mRNA (p = 0.0002) of fetal rats were higher in the severe fatigue group than in the control group. HE staining of the telencephalon of fetal rats in the pregnant fatigue group revealed sparse and irregular cell arrangement and increased gaps in the hippocampal primordial site. Conclusion: Pregnant fatigue rats had both physical fatigue and mental fatigue. Fatigue during pregnancy affects physical development and neurodevelopment of offspring. Further research should elucidate the mechanisms of pregnant fatigue and its effects on offspring. [ABSTRACT FROM AUTHOR]

Background: Postpartum fatigue is a common disorder worldwide and affects both physical and mental functioning. In breastfeeding women, Prolactin (PRL) is not only involved in immunoregulation, but also responsible for lactation. Prolactin levels in women with chronic fatigue are higher than normal, but a chronic fatigue state inhibits postpartum lactation in humans. Objectives: This paper explored the inhibition mechanism of lactation by postpartum fatigue in rats. Methods: Postpartum fatigue models were built by forcing mother rats to stand in water and divided into 3-hour, 9-hour and 15-hour per day fatigue groups according to the underwater time. Mother rats and their offspring were reunited in a dry cage for 90 minutes every 3 hours for feeding. The expression of PRL, PRL receptor (PRLR), Janus Kinase 2 (JAK 2), and Signal transducers and activators of transcription 5 (STAT5) mRNA were analyzed and the microstructure of mammary gland were observed under light and electron microscopy. Results: The expression of pituitary PRL mRNA and its downstream signaling pathway JAK2 and STAT5 mRNA were down-regulated in the severe postpartum fatigue rats. PRL mRNA responses were dose-related to duration of fatigue. The expression of PRLR mRNA increased. Postpartum fatigue led to functional degeneration of mammary gland. The breast lobules were shrunk and the number of alveoli were decreased. Few milk protein granules and fat droplets were observed in the cytoplasm under transmission electron microscope. Conclusion: Postpartum fatigue inhibits the lactation by down-regulating the expression of PRL and PRL-dependent signaling pathway in rats. [ABSTRACT FROM AUTHOR]

A checkerboard microdilution method, performed according to the recommendations of the National Committee for Clinical Laboratory Standards, was used to study the in vitro interaction of fluconazole and allicin in 24 fluconazole-resistant clinical isolates of Candida albicans, one experimentally induced strain S-1, and one ATCC type strain 10231. The interaction intensity was determined by spectrophotometric methods and visual reading of the checkerboard assay, and the nature of the interactions was assessed using two nonparametric approaches [fractional inhibitory concentration index (FICI) and DeltaE models]. Synergism was observed in 23 strains using FICI, and in 22 strains using DeltaE. The DeltaE model gave results consistent with FICI, but no antagonistic action was observed. The positive interactions were also confirmed by the time-killing test and agar diffusion in the selected strains. Moreover, the in vivo experiment showed that a combination of fluconazole and allicin exhibited a good synergism against C. albicans.