Fixed-Time Aperiodic Intermittent Control for Quasi-Bipartite Synchronization of Competitive Neural Networks.

This paper concerns a class of coupled competitive neural networks, subject to disturbance and discontinuous activation functions. To realize the fixed-time quasi-bipartite synchronization, an aperiodic intermittent controller is initially designed. Subsequently, by combining the fixed-time stability theory and nonsmooth analysis, several criteria are established to ensure the bipartite synchronization in fixed time. Moreover, synchronization error bounds and settling time estimates are provided. Finally, numerical simulations are presented to verify the main results.

Multiple roles for LaFeO3 in enhancing the Photoelectrochemical performance of WO3.

For photoelectrochemical (PEC) water splitting, constructing heterojunctions and loading co-catalysts are effective means to realizing sufficient light absorption, effective photogenerated carrier separation and fast charge transport. However, during implementation, the PEC performance of the catalyst is affected by both parasitic light absorption and reflection and the change in energy band structure due to the creation of new interfaces. Herein, in order to minimize the effect of recombination of photogenerated electron-hole pairs on the catalyst PEC performance due to the nascent interface arising from the co-catalyst compounding, WO3 and Ni/Co co-doped LaFeO3 (LFO) are constructed as heterojunctions, in which NiCo-LFO acts both as a part of the heterojunction to enhance photogenerated carrier separation and a co-catalyst to enhance the conductivity and modulate the surface state density at the catalyst-electrolyte interface. The current density of NiCo-LFO/WO3 reaches 3.92 mA cm-2, which is more than 7 times that of LFO/WO3. This work provides a reference for the efficient water splitting of B-site doped, especially the co-doped perovskite oxide as multifunctional roles integrated with conventional photoelectrodes.

Effects of Oligomeric Procyanidins From Lotus Seedpod on the Retrogradation Properties of Rice Starch.

The extent of retrogradation strongly affects certain physical and cooking properties of rice starch (RS), which are important to consumers. In this study, oligomeric procyanidins from lotus seedpod (LSOPC) was prepared and used to investigate its inhibitory effect on RS retrogradation. Various structural changes of RS during retrogradation were characterized by differential scanning calorimetry, low field nuclear magnetic resonance, X-ray diffraction, scanning electron microscopy, and Fourier transform infrared spectroscopy. The results showed LSOPC could effectively retard both short- and long-term retrogradation of RS, and its inhibitory effect was dependent on the administered concentration of LSOPC. Molecule simulation revealed the interactions of RS and LSOPC, which indicated that the competition of hydrogen bonds between RS and LSOPC was the critical factor for anti-retrogradation. This inhibitory effect and mechanism of action of LSOPC could promote its applications in the field of starch anti-retrogradation.

The inhibitory effect of the catechin structure on advanced glycation end product formation in alcoholic media.

Advanced glycation end products (AGEs) and their important intermediate products (α-dicarbonyl compounds) that are generated by the Maillard reaction are closely related to diabetes. Our study first investigated the mechanisms of the anti-glycation effects of epicatechin (EC), (-)-epicatechin gallate (ECG), (-)-epigallocatechin (EGC), and (-)-epigallocatechin gallate (EGCG) in an alcoholic environment. The results showed that catechins played an important role in the inhibition of AGE formation, and the effect of EC was the best. Their corresponding mechanisms included total antioxidant capacity (TAOC), 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging ability, trapping of methylglyoxal (MGO), protection of the protein structure, and inhibition of the activities of α-amylase, α-glucosidase, and ß-glucosidase, which were consistent with the study of molecular docking. This study will offer a theoretical basis for the applications of different types of catechins to alcoholic beverages as natural AGE formation inhibitors.

Moderate hyperoxia plays a protective role in lung bronchial epithelial cells.

PURPOSE: Oxygen therapy is commonly used in clinical settings, but several problems may result from improper use. Oxygen poisoning involves the initiation of a series of inflammatory reactions. In this study, we compared the effects of moderate hyperoxia (40% O2) and extreme hyperoxia (85% O2) on pulmonary bronchial epithelial cells. METHODS: Normal human tracheobronchial epithelium (NHBE) cells were exposed to hyperoxia (40% and 85%) for 24 hours, and their survival rates were determined by the colorimetic assay, MTT (3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide). The protein and mRNA levels of RelA, RelB, ASK1, TNF-α and secretory component (SC) were detected by immunohistochemical staining, western blot, and real-time polymerase chain reaction. RESULTS: The NHBE cell survival increased in the presence of moderate hyperoxia. RelA, RelB, ASK1, TNF-α and SC expressions were significantly higher in the 85% O2 group in comparison with the control group and the 40% O2 group. In the 40% O2 group, RelA, RelB, ASK1 and TNF-α were upregulated, but SC expression was not significantly different than that of the control group. However, compared with the 85% O2 group, SC expression was significantly lower in the 40% O2 group. CONCLUSION: These results suggest that moderate hyperoxia promotes proliferation in NHBE cells and activates TNF-α and downstream ASK1. Then TNF-α activates NF-κB and SC to play a protective role.

Structure-activity relationship of procyanidins on advanced glycation end products formation and corresponding mechanisms.

Nonenzymatic glycosylation (NEG) can generate advanced glycation end products (AGEs) and its intermediates α-dicarbonyl compounds, which contribute to the risk of diabetes. This study investigated the anti-glycation mechanisms and structure-activity relationship of (+)-catechin (CC) and (-)-epicatechin (EC). The results showed that the effect of CC on inhibiting AGEs was significantly better than that of EC (p < 0.05). By exploring the mechanism, we found that there was no significant difference in the ability of CC and EC to capture α-dicarbonyl compounds. But CC was found to be more efficient than EC to inhibit RO, OH and CHO radicals generation, which may be the primary reason that CC was more effective than EC on AGEs inhibition. What's more, CC showed better inhibitory effect on ß-glucosidase that was close to the molecular docking study. Our results will provide a theoretical foundation for development of different structure of procyanidins as natural AGEs inhibitors in food and medicine.

Reactive oxygen species induce injury of the intestinal epithelium during hyperoxia.

Long-term therapeutic hyperoxia may exert serious toxic effects on intestinal epithelial cells in vitro and in vivo. The aim of the present study was to investigate the cause of this intestinal injury under conditions of hyperoxia. Caco-2 cells were treated with different concentrations of hydrogen peroxide (H2O2) and 85% hyperoxia for 24 h. higher rates of injury of Caco-2 cells were observed in the hyperoxia and H2O2 groups compared with the control group. The reactive oxygen species (ROS) level of the hyperoxia group was significantly higher compared with that of the 400 µM H2O2 group. The protein and gene levels of RelA, RelB, hypoxia­inducible factor-1α, tumor necrosis factor-α and apoptosis signal­regulating kinase 1 were significantly higher in the hyperoxia and H2O2 groups compared with those in the control group. In conclusion, during hyperoxia, intestinal epithelial cells were destroyed and the levels of ROS were increased. Therefore, ROS may play an important role in intestinal injury in a hyperoxic environment.

Influence of reactive oxygen species on secretory component in the intestinal epithelium during hyperoxia.

Redox imbalance is established in various human diseases. Treatment of intestinal epithelial cells with hyperoxia for a prolonged period of time may cause serious effects on redox balance. Secretory component (SC) protein is secreted by intestinal epithelial cells, and has a vital role in mucosal immune systems and intestinal defense. The present study aimed to investigate the influence of reactive oxygen species (ROS) on intestinal epithelial cells and intestinal epithelial SC protein under hyperoxic conditions. Caco-2 cells were treated with increasing concentrations of hydrogen peroxide (H2O2) or 85% O2 (hyperoxia) for 24 h. Flow cytometry, immunohistochemistry staining, western blot analysis and reverse transcription-quantitative polymerase chain reaction were performed to detect the expression levels of SC protein. Significantly increased apoptosis and mortality rates were observed in hyperoxia- and H2O2-treated Caco-2 cells, as compared with the untreated control cells (P<0.05). Protein and mRNA expression levels of SC were significantly increased in hyperoxia- and H2O2-treated groups, as compared with the control group (P<0.05). During hyperoxia, intestinal epithelial cells were destroyed and ROS levels increased. Therefore, the results of the present study suggested that ROS might have an important role in intestinal injury in hyperoxic environments.