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Developing multifunctional hydrogel dressings with good biocompatibility and mechanical compatibility can accelerate skin healing and alleviate pain. Although hydrogel dressings can achieve a wound closure rate of nearly 90% in 15 days, there is room for improving their healing efficiency. Herein, we synthesized a novel hydrogel dressing by doping methacrylated gelatin (GelMA) with silver nanowires (AgNWs) via mechanical mixing and ultraviolet light curing. We abbreviated the GelMA/AgMWs hydrogels as GMANx, with "x" indicating the initial amount of AgNWs (w/v). We found that GMAN5, with an AgNWs content of 0.5 mg/mL, had potent antibacterial activity (nearly 100% against Staphylococcus aureus and Escherichia coli), displayed good biocompatibility, and achieved a wound closure rate of 99.6% within 14 days (circular skin wounds with a diameter of 10 mm). The AgNWs not only improved the mechanical property of the hydrogel wound dressing but also made it conductive. Thanks to its excellent strain electrical response (gage factor (GF) = 2.3 under low strain conditions of 0–70%) and temperature electrical response (temperature coefficient of resistance (TCR) = 3.68%/°C within 30–40 °C), the GelMA5 hydrogel dressing has potential applications for sensing changes in the wound. [ABSTRACT FROM AUTHOR]

Wound healing is a complex process composed of different stages, which involves extensive communication between the different cellular factors of the extracellular matrix (ECM). The radio frequency electromagnetic field (RF-EMF) has been used to accelerate the wound-healing process and it has been found to enhance cell alignment and mobility. The conventional methods for cell mobility analysis in an electromagnetic field generated by a radiation source are not advisable due to the low-precision, nonuniform distribution of the field, low efficiency of the analysis in batch and the lack of system integration for autonomous on-body operation. Here, a novel and versatile electromagnetic exposure system integrated with a microfluidic chip was fabricated to explore the EMF-induced response. A gradient electromagnetic field in a two-dimensional plane has been successfully established in the microchambers placed along the field line. In this work, by deploying our radiation experiments in vitro, we validated the on-chip monitoring of cell response to exposure. This electromagnetic field was simulated and human amniotic epithelial cells (HAECs) were cultured in different microchambers for continuous exposure to the electromagnetic field excited by a monopole RF antenna (1.8 GHz). New protrusions were generated and an obvious increase in filopodia with the increased field intensity was investigated. Meanwhile, the variation in intracellular Ca2+ concentration under the electromagnetic field was examined. The inhibitory effect of the Ca2+ circulation was further inspected to reveal the potential downstream signaling pathway in the RF-EMF-related bioassay, suggesting that cytoskeletal dynamics of cells under exposure are highly associated with the EGF receptor (EGFR)-cytoskeleton downstream signaling pathway. Finally, the field-induced cell elongation and alignment parallel to the field direction were observed. Additionally, the subsequent recovery (field withdrawal) and re-establishment (field re-exposure) were explored. These results indicated that this reliable and versatile exposure system for bioassay could achieve precise and high-throughput detection of the RF-EMF-induced cytoskeletal reorganization in vitro and evaluate the possible health risk from RF-EMF exposure. [ABSTRACT FROM AUTHOR]

An NMR method based on the gradient-based broadening fingerprint using line shape enhancement (PROFILE) is put forward to precisely and sensitively study hydrogel swelling under restricted conditions. This approach achieves a match between the resonance frequency and spatial position of the sample. A three-component hydrogel with salt ions was designed and synthesized to show the monitoring more clearly. The relationship between the hydrogel swelling and the frequency signal is revealed through the one-dimensional imaging. This method enables real-time monitoring and avoids changing the swelling environment of the hydrogel during contact. The accuracy of this method may reach the micron order. This finding provides an approach to the rapid and non-destructive detection of swelling, especially one-dimensional swelling, and may show the material exchange between the hydrogel and swelling medium. [ABSTRACT FROM AUTHOR]

In order to improve the effective extraction of fetal heart rate and prevent fetal distress in utero, a study of fetal heart rate feature extraction based on wavelet transform to prevent fetal distress in utero was proposed. This paper adopts a fetal heart rate detection method based on the maximum value of the binary wavelet transform modulus. The method is simulated by the Doppler fetal heart signal obtained from the clinic. Compared with the original curve, the transformed curve can roughly see the change rule of the original signal and identify the peak point of the signal, but due to the large disturbance of the peak point, the influence on the computer processing is also great. The periodicity of the transformed signal is greatly enhanced, making it easier to deal with the computation. A total of 300 pregnant women with full-term fetal heart monitoring from January 2018 to January 2020 were selected as the research subjects and divided into the observation group and the control group. The observation group consisted of 100 patients with abnormal fetal heart monitoring, and the control group consisted of 200 patients with normal fetal heart monitoring. The uterine contractions and fetal heart rate were recorded, and the incidence of fetal distress, cesarean section, neonatal asphyxia, and amniotic fluid and fecal contamination were observed. The incidence of fetal distress, cesarean section, neonatal asphyxia, and amniotic fluid fecal stain in the observation group were significantly higher than those in the control group. Fetal heart monitoring can accurately judge the situation of the fetus in pregnant women and timely diagnose the abnormal fetal heart rate, which has a better effect on the prognosis of perinatal infants and can reduce their mortality. It can effectively solve the problems existing in the autocorrelation algorithm and extract the fetal heart rate more accurately. It is an effective improved scheme of fetal heart rate extraction. It is very helpful in preventing fetal distress in utero. [ABSTRACT FROM AUTHOR]

The preparation of flexible nano-scale carbon materials with good energy storage properties using biomass is a challenging task. Herein, we developed a simple and efficient strategy for preparing high-performance green nano-scale carbon fibrous materials (CFs). A fractionated process is performed to obtain lignin with different chemical structures, including active chemical groups, branched structure, molecular weight and molecular spatial conformation. The fractionated lignin is phosphatized and mixed with cellulose acetate as a precursor material to prepare green nano-scale CFs by electrospinning. This strategy completely gets rid of the dependence of petroleum-based polymer spinning aids and endows biomass-based carbon materials with complete fibrous morphologies, uniform diameter, large surface area, good flexibility and excellent energy storage properties. The specific capacitance of biomass-based CFs as three-electrode capacitance reaches 363.1 F g−1. At a power density of 800 W kg−1, the biomass-based CF supercapacitor device delivers an energy density of 31.2 W h kg−1. Furthermore, the biomass-based CFs exhibit great potential for flexible free-standing supercapacitor with capacitance retention of ∼98% after 10 000 cycles. [ABSTRACT FROM AUTHOR]

Lignin-first is a strategy for producing value-added phenolics and high-quality bio-oils from lignin. To contribute to this strategy, we investigated the effects of ultrasound acoustic cavitation on depolymerization of organosolv lignin to phenolic monomers and low molecular weight lignin bio-oils. We achieved the highest lignin bio-oil yield of 56.9 wt% at a temperature of 250 °C, a reaction time of 6 h, and an ultrasonic power of 90 W. Moreover, the obtained lignin bio-oils had low molecular weight, narrow molecular weight distribution and lack of ether linkages, which are the characteristics suitable as a source of liquid bio-oil fuels. Finally, the prominent phenolic monomers in liquid bio-oil, including phenol, 2-(1-methylethyl)-phenol and benzene, 1,2,3-trimethoxy-5-methyl, were identified in lignin bio-oil. Unlabelled Image • Lignin is depolymerized in different media under green ultrasonic assisted method. • Yield of lignin bio-oil was promoted with ultrasound acoustic cavitation. • 56.9 wt% yield of bio-oil with 2.07 wt% monomers yield is obtained without catalyst. • Oligomers in the bio-oil are mainly low molecular weight and high H/C ratio. [ABSTRACT FROM AUTHOR]