Optimal control of non-linear systems through hybrid cell-mapping/artificial-neural-networks techniques

In this paper, a real-time optimal control technique for non-linear plants is proposed. The control system makes use of the cell-mapping (CM) techniques, widely used for the global analysis of highly non-linear systems. The CM framework is employed for designing approximate optimal controllers via a control variable discretization. Furthermore, CM-based designs can be improved by the use of supervised feedforward artificial neural networks (ANNs), which have proved to be universal and efficient tools for function approximation, providing also very fast responses. The quantitative nature of the approximate CM solutions fits very well with ANNs characteristics. Here, we propose several control architectures which combine, in a different manner, supervised neural networks and CM control algorithms. On the one hand, different CM control laws computed for various target objectives can be employed for training a neural network, explicitly including the target information in the input vectors. This way, tracking problems, in addition to regulation ones, can be addressed in a fast and unified manner, obtaining smooth, averaged and global feedback control laws. On the other hand, adjoining CM and ANNs are also combined into a hybrid architecture to address problems where accuracy and real-time response are critical. Finally, some optimal control problems are solved with the proposed CM, neural and hybrid techniques, illustrating their good performance.

Gastroprotective potential of Buddleja scordioides Kunth: Effects into the modulation of antioxidant enzymes and inflammation markers in an in vivo model

Ethnopharmacological relevance: A common plant used to treat several gastric disorders is Buddleja scordioides Kunth,commonly known as salvilla. Aim of thes tudy: To detect inflammatory markers,in order to evaluate the gastroprotective potential of salvilla infusions,as this could have beneficial impact on the population exposed to gastric ulcers and colitis. Materials and methods: The present work attempted infusions were prepared with B. scordioides (1% w/w) lyophilized and stored.Total phenolic content and GC–MS analysis were performed. Wistar rats were divided into five groups a negative vehicle control,an indomethacin group,and three experimental groups,named preventive,curative,and suppressive. All rats were sacrificed under deep ether anesthesia(6h)after the last oral administration of indomethacin/infusion.The rat stomachs were promptly excised,weighed,and chilled in ice-cold and 0.9%NaCl.Histological analysis,nitrites quantification and immunodetection assays were done. Results: B.scordioides infusions markedly reduced the visible hemorrhagic lesions induced byindomethacin in rat stomachs,also showed down-regulation of COX2, IL-8 and TNFα and up-regulation of COX-1with a moderate down-regulation of NFkB and lower amount of nitrites.However,this behavior was dependent on the treatment,showing most down-regulation of COX-2,TNFα and IL-8 in the curative treatment;more down-regulation of NF-kB in the preventive treatment;and more up-regulation of COX-1 for the suppressor and preventive treatments. Conclusion: The anti-inflammatory potential of B. scordioides infusions could be related with the presence of polyphenols as quercetin in the infusion and how this one is consumed.