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PublicationCorryocactus brevistylus (K. Schum. ex Vaupel) Britton & Rose (Cactaceae): Antioxidant, Gastroprotective Effects, and Metabolomic Profiling by Ultrahigh-Pressure Liquid Chromatography and Electrospray High Resolution Orbitrap Tandem Mass Spectrometry(Frontiers Media S.A., 2020-04-08)
;Hernandez M. ;Ticona J. ;Cortes C. ;Simirgiotis M. ;Borquez J. ;Echeverría J.Sepulveda B.Corryocactus brevistylus (K. Schum. ex Vaupel) Britton & Rose (Cactaceae) is a shrubby or often arborescent cactus popularly known as “sancayo” and produce an edible fruit known as “Sanky” which is consumed in Arequipa-Perú. The purpose of this study was to report the gastroprotective activity and relate this activity to the antioxidant capacity and presence of phenolic compounds for the first time. A metabolomic profiling based on Ultrahigh-pressure liquid chromatography and electrospray high resolution mass spectrometry, and the antioxidant activities (DPPH, ABTS, and FRAP), ascorbic acid content, total phenolics and flavonoids contents, and the mode of gastroprotective action of the Sanky fruit including the involvement of prostaglandins, nitric oxide, and sulfhydryl compounds is reported. Thirty-eight compounds were detected in the ethanolic extract including 12 organic acids, nine hydroxycinnamic acids, three isoamericanol derivatives, six flavonoids, five fatty acids, and two sterols. The results of the biological tests showed that the ethanolic extract had antioxidant capacity and gastroprotective activity on the model of HCl/EtOH-induced gastric lesions in mice (at 10, 25, 50, and 100 mg/kg). The effect elicited by the extract at 50 mg/kg was reversed by indometacin and N-ethylmaleimide but not by NG-nitro-L-arginine methyl ester suggesting that sulfhydryl groups and prostaglandins are involved in the mode of gastroprotective action. In conclusion, our study proves that C. brevistylus pears have some gastroprotective and antioxidant capacities and consumption is recommended for the presence of several bioactive compounds. -
PublicationExplosion of power capacitors in a change of transformers with reactive power compensationIn industrial activities, the load increase with a more production requirements and overloading, however, in some case the power transformer requires to change for a failure or a contingency stage. In this case, a real engineering failure analysis is done for the shunt capacitors explosion in an industrial facility. A new methodology is proposed for the Engineering failure Analysis for capacitors explosions with overloading power transformers condition, the individual and system assessment with an international standard review is developed for a better understanding in the solution proposal. With this new methodology the following Standards should be updated: IEC 60931, IEC 60871, IEC 60110, IEC 60143, IEC 60252, IEC 60358, IEC 61017, IEC 61048 and IEC 61049. The degradation analysis for the power transformer are considered too with the following international standards analysis: Laboratec, Duval, ABNT IEC 60599, IEEE Rogers, IEC 60599 and CIGRE CS 15. A new recommendation for an international standard is proposed, for the critical scenario, contingency stage and finally the solution with the methodology in a real case study in a Gold mining located in Colombia.
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PublicationFlexibility as an element of change for creativity and innovation in the university classroom(Associacao Iberica de Sistemas e Tecnologias de Informacao, 2019-07-01)
;Vega E.A.P. ;Caro C.K.M.López T.L.B.This article takes us to university learning environments to delve into the in-depth knowledge of how teachers think, act and conceive creativity. The aim is to analyze the new challenges in higher education in reference to teachers’ perception of flexibility as an element to generate creativity and innovation. The type of research is descriptive, with sampling by clusters. The creativity self-evaluation questionnaire used has 47 items, which measured the dimensions of flexibility, conceptualization of creativity and innovation, teacher training, objectives and contents, integral formation of students, didactic interaction and methodology. The main finding was the applicability of teachers in reference to flexibility from their teacher training, using active methodologies for student training. Concluding that there is a moderate relationship between flexibility and creativity and innovation, didactic integration, objectives and content. -
PublicationMFSRank: An unsupervised method to extract keyphrases using semantic information(Springer, 2011-12-06)
;Barreda D.This paper presents an unsupervised graph-based method to extract keyphrases using semantic information. The proposed method has two stages. In the first one, we have extracted MFS (Maximal Frequent Sequences) and built the nodes of a graph with them. The weight of the connection between two nodes has been established according to common statistical information and semantic relatedness. In the second stage, we have ranked MFS with traditionally PageRank algorithm; but we have included ConceptNet. This external resource adds an extra weight value between two MFS. The experimental results are competitive with traditional approaches developed in this area. MFSRank overcomes the baseline for top 5 keyphrases in precision, recall and F-score measures. © 2011 Springer-Verlag.