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Protonic ceramic electrochemical cells (PCECs) have received considerable attention as they can directly generate electricity and/or produce chemicals. Development of the electrodes with the trifunctionalities of oxygen reduction/evolution and nonoxidative ethane dehydrogenation is yet challenging. Here these findings are reported in the design of trifunctional electrodes for PCECs with a detailed composition of Mn0.9Cs0.1Co2O4-δ (MCCO) and Co3O4 (CO) (MCCO-CO, 8:2 mass ratio). At 600 °C, the MCCO-CO electrode exhibits a low area-specific resistance of 0.382 Ω cm2 and reasonable stability for ≈105 h with no obvious degradation. The single cell with the MCCO-CO electrode shows an encouraging peak power density of 1.73 W cm-2 in the fuel cell (FC) mode and a current density of -3.93 A cm-2 at 1.3 V in the electrolysis cell (EC) mode at 700 °C. Moreover, the MCCO-CO cell displays promising operational stability in FC mode (223 h), EC mode (209 h), and reversible cycling stability (52 cycles, 208 h) at 650 °C. The MCCO-CO single cell shows an encouraging ethane conversion to ethylene (with a conversion of 40.3% and selectivity of 94%) and excellent H2 production rates of 4.65 mL min-1 cm-2 at 1.5 V and 700 °C, respectively, with reasonable Faradaic efficiencies.
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In this study, a novel fresh-keeping edible film was prepared using egg yolk (EY) and chitosan (CS) with varying concentrations of curcumin (Cur) for food packaging. The addition of Cur notably enhanced tensile strength, elongation at break, and water resistance from 15.70 MPa to 24.24 MPa, 43.79 % to 63.69 %, and 1.599 g·mm·(m2·h·kPa)-1 to 1.541 g·mm·(m2·h·kPa)-1, respectively. Cur also impacted moisture content, swelling degree, and film color. SEM revealed a uniform distribution of Cur, creating a smooth and dense film surface. FT-IR analysis suggested that hydrogen bonding facilitated Cur integration into the film network. The films demonstrated excellent UV-blocking and antioxidant properties attributed to Cur's chromogenic and phenolic hydroxyl groups. Consequently, they effectively inhibited lipid oxidation and weight loss in meat, thereby prolonging the shelf-life of chilled pork by at least 2 d. In conclusion, this study provided a simple and cost-effective idea to incorporate actives with EY as a natural emulsifier, presenting an effective solution for developing active packaging materials to enhance the safety and quality of meat products.
Assuntos
Antioxidantes , Quitosana , Curcumina , Filmes Comestíveis , Gema de Ovo , Embalagem de Alimentos , Curcumina/química , Curcumina/farmacologia , Quitosana/química , Gema de Ovo/química , Embalagem de Alimentos/métodos , Animais , Antioxidantes/química , Antioxidantes/farmacologia , Suínos , Carne de Porco/análise , Conservação de Alimentos/métodosRESUMO
Alcea rosea L. is a traditional flower with a long cultivation history. It is extensively cultivated in China and is widely planted in green belt parks or used as cut flowers and potted ornamental because of its rich colors and flower shapes. Double-petal A. rosea flowers have a higher aesthetic value compared to single-petal flowers, a phenomenon determined by stamen petaloid. However, the underlying molecular mechanism of this phenomenon is still very unclear. In this study, an RNA-based comparative transcriptomic analysis was performed between the normal petal and stamen petaloid petal of A. rosea. A total of 3,212 differential expressed genes (DEGs), including 2,620 up-regulated DEGs and 592 down-regulated DEGs, were identified from 206,188 unigenes. Numerous DEGs associated with stamen petaloid were identified through GO and KEGG enrichment analysis. Notably, there were 63 DEGs involved in the plant hormone synthesis and signal transduction, including auxin, cytokinin, gibberellin, abscisic acid, ethylene, brassinosteroid, jasmonic acid, and salicylic acid signaling pathway and 56 key transcription factors (TFs), such as MADS-box, bHLH, GRAS, and HSF. The identification of these DEGs provides an important clue for studying the regulation pathway and mechanism of stamen petaloid formation in A. rosea and provides valuable information for molecular plant breeding.
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Flores , Perfilação da Expressão Gênica , Flores/genética , Flores/crescimento & desenvolvimento , Flores/anatomia & histologia , Transcriptoma , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Reguladores de Crescimento de Plantas/metabolismoRESUMO
In this study, chitosan coatings with different degrees of deacetylation (DD, 88.1 % and 95.2 %) were electrostatically sprayed on sweet cherries to evaluate their impacts on postharvest characteristics and internal metabolism. The results showed that chitosan coating could effectively delay the change of weight, color, firmness, and maintain the content of total phenols, flavonoids and titratable acids, and inhibit the activities of ß-galactosidase and polyphenol oxidase during cold storage. The storage qualities and physiological activities of sweet cherry were significantly correlated with the contents of sorbitol, 4-hydroxycinnamic acid, hydrogenated hydroxycinnamic acid, tyrosine, proline, glutamine, phenylalanine, and other metabolites. Chitosan coating may modulate fruit quality by inhibiting the energy metabolism, accelerating the accumulation of carbohydrates, and promoting the metabolism of phenylalanine and flavonoid. Especially, chitosan coating with 88.1 % DD had better wettability on sweet cherry's peel and displayed more obvious preservation effect through stronger metabolic regulation ability.
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Quitosana , Prunus avium , Conservação de Alimentos/métodos , Quitosana/farmacologia , Frutas , Flavonoides/metabolismo , Fenilalanina/metabolismoRESUMO
The commercialization of solid oxide fuel cells (SOFCs) that run on liquid hydrocarbon fuels is hindered by the poor coking tolerance of the state-of-the-art anode. Among the strategies developed, modulating the reforming reaction site's local steam/carbon ratios to enhance the coking tolerance is efficient but challenging. Here we report our rational design of a ceria-based catalyst (with a nominal composition of Ce0.95Ru0.05O2-δ, CR5O) that demonstrates remarkable tolerance to coking while maintaining excellent activity for direct utilization of liquid fuels in SOFCs. Under operating conditions, the catalyst is transformed to a partially reduced oxide frame covered with Ru nanoparticles (Ru/Ce0.95Ru0.05-xO2-δ, Ru/CR5-xO), as confirmed by experimental analyses. The Ru/CR5-xO demonstrates excellent self-hydration capability to remove the coke. When applied to the Ni-yttria-stabilized zirconia (Ni-YSZ) anode of an SOFC with liquid fuels, the catalyst enables excellent performance, achieving a peak power density of 1.010 W cm-2 without coking for â¼200 h operation (on methanol) at 750 °C. Furthermore, density functional theory calculations reveal that the high activity and coking tolerance of the Ru/CR5-xO catalyst-coated Ni-YSZ anode is attributed to the reduced energy barrier for the rate-limiting step and the formation of a COH intermediate for rapid carbon removal.
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Surfactants are always added to coating formulations to ensure good adhesion of edible coatings to a product's surface and to maintain freshness. In this study, the effects of the mix surfactants Tween 20 and Span 80 with different hydrophile-lipophile balance (HLB) values on the film-forming ability, wettability, and preservation capacity of blueberry sodium alginate coating were investigated. The results indicated that Tween 20 obviously ensured favorable wettability and improved the uniformity and mechanical properties of the resulting film. While the addition of Span 80 reduced the mean particle size of the coating, enhanced the water resistance of the film, and helped to reduce blueberry weight loss. A sodium alginate coating with low viscosity and medium HLB could better inhibit the galactose, sucrose, and linoleic acid metabolism of blueberries, reduce the consumption of phenols, promote the accumulation of flavonoids, and thus display superior coating performance. In summary, sodium alginate coating with medium HLB had comprehensive advantages in film-forming ability and wettability and was conducive to the fresh-keeping role.
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Edible films based on egg white protein (EWP) were prepared, and it were modified by high-intensity ultrasound (HIUS) to improve the functional properties. The findings indicated the properties of EWP films were improved at the appropriate time of HIUS treatment. With the increase of ultrasonic time, water vapor permeability (WVP) and tensile strength (TS) of EWP films ascended and then declined, and the best performance (3.30 g·mm/ m2·h·KPa for WVP, and 7.28 MPa for TS) was achieved when ultrasonic time was 10 min. Thermogravimetric analysis exhibited ultrasound could enhance the thermal stability of EWP films. The SEM reflected moderate ultrasonic treatment could make the EWP films smoother. The FTIR spectroscopy and X-ray diffraction patterns of EWP films were changed by HIUS, which illustrated the secondary structure of the protein was altered. The transverse relaxation curve obtained by LF-NMR analysis showed the tightness between water and the films.
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Proteínas do Ovo , Vapor , Proteínas do Ovo/química , Permeabilidade , Resistência à Tração , Difração de Raios XRESUMO
BACKGROUND: We evaluated the improvement in the gray and white matter functional areas in children with cerebral palsy (CP) after common carotid artery sympathetic neural network ablation. We also analyzed the relationship between the values of the diffusion kurtosis imaging (DKI) parameters and clinical signs in children with CP. METHODS: We collected data from 22 children with unilateral spastic CP who had undergone common carotid sympathetic neural network ablation in our hospital from January 1, 2014 to December 1, 2018, using magnetic resonance kurtosis imaging technology parameters. RESULTS: The study found that the changes from preoperatively to postoperatively in the kurtosis fractional anisotropy (KFA) values for the frontal lobe, parietal lobe, temporal lobe, internal sac forelimb, and corpus callosum were statistically significant. However, the changes in the internal sac forelimb, corpus callosum, and KFA values were not statistically significant. The changes from preoperatively to postoperatively in the mean kurtosis (MK) values for the frontal lobe, parietal lobe, temporal lobe, hindlimb of the internal capsule, corpus callosum, and caudate nucleus were statistically significant. However, the MK values for the forelimb, corpus callosum, and thalamus were not statistically significant. The 66-item gross motor function measure scores correlated negatively with the KFA value and positively with the MK value. CONCLUSION: Therefore, it can be concluded that DKI technology can more accurately reflect the gray and white matter damage in children with CP, and the DKI parameters can be used as a monitoring and evaluation index for children with CP.
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Artéria Carótida Primitiva/inervação , Substância Cinzenta/diagnóstico por imagem , Simpatectomia/métodos , Substância Branca/diagnóstico por imagem , Estudos de Casos e Controles , Núcleo Caudado/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Paralisia Cerebral , Criança , Pré-Escolar , Corpo Caloso/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Cápsula Interna/diagnóstico por imagem , MasculinoRESUMO
The pathological mechanism of vascular cognitive impairment (VCI) involves ischemic lesions in the hippocampus. Prostaglandin E1 (PGE1) serves roles in the promotion of vascular endothelial growth factor (VEGF) expression, angiogenesis and enhances blood flow to ischemic regions. However, the effect of PGE1 on cognitive function in VCI rats and the underlying mechanism are unknown. In the current study, learning and memory function in VCI rats treated by lipoPGE1 injection was assessed through Morris Water Maze test. Furthermore, the histological alterations, blood vessel numbers in the hippocampal CA1 region and relative VEGF protein and mRNA expression were researched. The results confirmed that VCI rats treated with lipoPGE1 presented improved cognitive function, less neuronal cell loss, a greater number of blood vessels in the hippocampal region and higher VEGF protein and mRNA expression. However, the role of lipoPGE1 in VCI rats can be inhibited by SU5416 (a specific VEGFR2 antagonist). The results indicated that lipoPGE1 may alleviate cognitive deficits in VCI rats. The underlying mechanism may be associated with angiogenesis promoted by lipoPGE1, which may involve the VEGF/VEGFR pathway. These findings may have therapeutic implications for cognitive impairment induced by hypoperfusion or chronic ischemic lesions.
Assuntos
Alprostadil/uso terapêutico , Disfunção Cognitiva/tratamento farmacológico , Neovascularização Fisiológica , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Alprostadil/farmacologia , Animais , Região CA1 Hipocampal/efeitos dos fármacos , Região CA1 Hipocampal/patologia , Região CA1 Hipocampal/fisiopatologia , Disfunção Cognitiva/genética , Disfunção Cognitiva/fisiopatologia , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Neovascularização Fisiológica/efeitos dos fármacos , Perfusão , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Memória Espacial/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/genéticaRESUMO
Previous studies have demonstrated that prostaglandin E1 (PGE1) has a neuroprotective effect on cerebral ischemia. However, it remains unknown whether PGE1 promotes angiogenesis and neurogenesis after ischemic stroke. In this study, adult male Sprague-Dawley rats were subjected to permanently distal middle cerebral artery occlusion (MCAO). Rats were treated with lipo-prostaglandin E1(lipo-PGE1, 10 µg/kg/d) or the same volume of 0.9% saline starting 24 hours after MCAO daily for 6 consecutive days. All rats were injected 5'-bromo-2'-deoxyuridine (BrdU, 50 mg/kg) intraperitoneally every 12 hours for 3 consecutive days before being sacrificed. At 7 and 14 days after MCAO or sham-operation, rats were sacrificed. Post-stroke neurological outcome, infarction volume, angiogenesis and neurogenesis were evaluated. Treatment with lipo-PGE1 significantly increased the vascular density in the peri-infarct areas at 7 and 14 days after MCAO. The lipo-PGE1 treatment significantly enhanced the proliferation and migration of endogenous neural stem cells in the ipsilateral subventricular zone. The neural stem cells associated with blood vessels closely within a neurovascular niche in lipo-PGE1-treated rats after stroke. The lipo-PGE1 treatment also significantly improved the neurological recovery after MCAO. These results indicate that treatment with lipo-PGE1 promotes post-stroke angiogenesis, neurogenesis and their interaction, which would contribute to neurological recovery after cerebral infarction. Our study provides novel experimental evidences for the neuroprotective roles of PGE1 in ischemic stroke.