Browsing by Type "Controlled Vocabulary for Resource Type Genres::texto::revista::artículo original"
  • Publication
    Bio-Mechatronics Design and Manufacturing of Arm Exoskeleton with Electro-Pneumatic Mechanism for Passive Rehabilitation
    ( 2024-01-01)
    Nacarino A.
    ;
    Nacarino A.
    ;
    La-Rosa A.
    ;
    Quispe Y.
    ;
    Castro K.
    ;
    Valer F.S.
    ;
    Cornejo J.
    ;
    Cornejo J.
    ;
    Cornejo J.
    ;
    Vargas M.
    ;
    Castro R.
    ;
    Palomares R.
    ;
    Palomares R.
    ;
    Sanchez B.
    ;
    Allcca D.
    ;
    Nacarino G.
    ;
    Cruz-Vargas J.A.D.L.
    Exoskeletons are crucial for providing intensive and consistent rehabilitation over a longer period and may be able to treat the patient without the presence of the therapist compared to manual therapy. This approach allows for frequent treatment reducing several costs. Therefore, this study aimed to examine the passive elbow rehabilitation of lateral epicondylitis patients, usability, and bioinspired design, to develop a mechatronics system with three rehabilitation positions. Regarding the biomechanical fundamentals of the elbow joint and as an engineering sustain, Computer-Aided Design (CAD) was made, consisting of Finite Element Analysis (FEA), anthropometric, ergonomic, and assembly analysis. The results showed that for the three rehabilitation positions, FEA showed von Mises stress less than the elastic modulus by a 103-factor resulting in no permanent deformation. Position 1, 2, and 3 produced angular displacements of 27°, 16.5° and 31° respectively with a total of 74.5°. An arm exoskeleton for passive rehabilitation of the elbow was developed using a pneumatic cylinder and an AD8832 electromyography (EMG) sensor, capable of detecting the EMG peak point to activate or deactivate the 24 V Arduino relay to flex or extend the elbow based on the positions. A total angular displacement of 74.5° was obtained instead of the simulated version 84.63°, with an error margin of 11.96%. The force during the three rehabilitation positions was 18 N exerted by the air compressor at a 6-bar constant pressure, and due to the use of choke valves.
  • Publication
    Flavonoid diversity in bitter and debittered seeds of Andean lupin (Lupinus mutabilis Sweet)
    ( 2024-06-01)
    Tian Y.
    ;
    Cortés-Avendaño P.
    ;
    Yang B.
    ;
    Glorio-Paulet P.
    ;
    Repo-Carrasco-Valencia R.
    ;
    Suomela J.P.
    Seeds of ten Andean lupin (Lupinus mutabilis Sweet) ecotypes were collected from different regions of Peru and treated with an aqueous debittering method. Both untreated and treated seeds were analyzed by using LC-MS to investigate flavonoid profiles of different ecotypes and impact of debittering process on these compounds. Thirteen isoflavones (mainly as glycosides of genistein and methoxy-genistein) and eight flavones (glycosylated apigenins and methyl-luteolins) were characterized as the main flavonoids in the seed samples. The untreated lupin seeds contained 187–252 mg/100 g (dry weight) of flavonoids. The main difference among lupin ecotypes was observed in the levels of genistein-malonylhexoside, methoxy-genistein-malonylhexoside, and methyl-luteolin-malonylhexoside. After the debittering treatment, the total flavonoid content in the seeds was decreased to 125–203 mg/100 g dry weight, the aglycones of genistein, methoxy-genistein, and methyl-luteolin being the key distinguishing compounds of ecotypes. The aqueous treatment was effective in degrading flavonoid glycosides and releasing the corresponding aglycones.
  • Publication
    Formative Research to Strengthen Enquiry Competence in University Students
    ( 2022-11-01)
    Campos-Uga O.
    ;
    Campos-Ugaz W.A.
    ;
    Ronald M.H.
    ;
    Doig S.G.A.
    ;
    Ortíz J.B.F.
    ;
    Saavedra-López M.A.
    ;
    Garay-Argandoña R.
    The purpose of the study was to demonstrate the effectiveness of formative research in strengthening enquiry competence in university students. In this sense, a single-group design with pre-test and post-test was used, with a purposive sample of 102 subjects. The instrument used was a rubric, characterised by very high valuations, in terms of validity criteria (0.917) and reliability (0.869). The results obtained exceeded expectations, which were corroborated by the Wilcoxon statistical test; since the theoretical significance α = 0.05 is superlative, when compared to the observed significance, Sig.=000; consequently, the null hypothesis was categorically rejected. In short, the proposal, consisting of five stages: sensitisation, adoption, interaction, evaluation and confrontation, proved its effectiveness in the enhancement of investigative knowledge, such as the problematisation-theorisation-checking of reality. Undoubtedly, great advances in initial training that have an impact not only in raising the quality of scientific production, but also in making sustainable the development of research skills for subsequent performance in the professional field and for improving quality in universities.
  • Publication
    Is what you see what you get? Assessing external morphological identification of devil rays captured by small-scale fisheries in northern Peru using DNA barcoding
    ( 2023-09-01)
    Alfaro-Cordova E.
    ;
    Alfaro-Cordova E.
    ;
    Cañedo-Apolaya R.M.
    ;
    Alfaro-Shigueto J.
    ;
    Alfaro-Shigueto J.
    ;
    Mangel J.C.
    ;
    Carrillo O.
    ;
    Sarmiento D.
    ;
    Velez-Zuazo X.
    Peru has globally important elasmobranch fisheries, and mobulids are no exception. However, little is known about Peru’s small-scale mobulid fisheries. Mismatches between fishing reports and studies regarding species occurrence suggest a problem in identification methodologies of mobulids at the species level. This is supported by evidence of external resemblance between species, landings of incomplete bodies, and the use of a single name for the five species known to occur in Peruvian waters (“Manta” for Mobula birostris, Mobula munkiana, Mobula mobular, Mobula tarapacana and Mobula thurstoni). Given the need for improved conservation and management measures of mobulids in Peru, we tested the applicability of DNA barcoding combined with morphological identification to better understand mobulid catches by small-scale fisheries in north Peru. A total of 137 samples of muscle tissue from mobulids captured during fishing activities were collected of which 99 amplified and analysed for Cytochrome C Oxidase Subunit I (COI). Samples of the five species known to occur in Peru were obtained, confirming captures of all of them by local fisheries. Morphological identification allowed us to correctly identify more than 94% of specimens to the species level even though most of them arrived butchered (e.g., only pectoral fins). Increased capacity building and training for morphological identification of mobulid species by field observers, authorities, and fishermen, combined with molecular tools, is highly recommended to avoid mistakes in landings reports and to correctly enforce conservation measures for these species.
  • Publication
    Low-cycle fatigue life assessment of SAC solder alloy through a FEM-data driven machine learning approach
    ( 2024-02-20)
    Ruiz-Jacinto V.S.
    ;
    Gutiérrez-Valverde K.S.
    ;
    Aslla-Quispe A.P.
    ;
    Burga-Falla J.M.
    ;
    Alarcón-Sucasaca A.
    ;
    Huamán-Romaní Y.L.
    Purpose: This paper aims to present the novel stacked machine learning approach (SMLA) to estimate low-cycle fatigue (LCF) life of SAC305 solder across structural parts. Using the finite element simulation (FEM) and continuous damage mechanics (CDM) model, a fatigue life database is built. The stacked machine learning (ML) model's iterative optimization during training enables precise fatigue predictions (2.41% root mean square error [RMSE], R2 = 0.975) for diverse structural components. Outliers are found in regression analysis, indicating potential overestimation for thickness transition specimens with extended lifetimes and underestimation for open-hole specimens. Correlations between fatigue life, stress factors, nominal stress and temperature are unveiled, enriching comprehension of LCF, thus enhancing solder behavior predictions. Design/methodology/approach: This paper introduces stacked ML as a novel approach for estimating LCF life of SAC305 solder in various structural parts. It builds a fatigue life database using FEM and CDM model. The stacked ML model iteratively optimizes its structure, yielding accurate fatigue predictions (2.41% RMSE, R2 = 0.975). Outliers are observed: overestimation for thickness transition specimens and underestimation for open-hole ones. Correlations between fatigue life, stress factors, nominal stress and temperature enhance predictions, deepening understanding of solder behavior. Findings: The findings of this paper highlight the successful application of the SMLA in accurately estimating the LCF life of SAC305 solder across diverse structural components. The stacked ML model, trained iteratively, demonstrates its effectiveness by producing precise fatigue lifetime predictions with a RMSE of 2.41% and an “R2” value of 0.975. The study also identifies distinct outlier behaviors associated with different structural parts: overestimations for thickness transition specimens with extended fatigue lifetimes and underestimations for open-hole specimens. The research further establishes correlations between fatigue life, stress concentration factors, nominal stress and temperature, enriching the understanding of solder behavior prediction. Originality/value: The authors confirm the originality of this paper.
  • Publication
    Variants in the N-acetyltranferase 2 gene, acetylator phenotypes and their association with tuberculosis: Findings in Peruvian patients
    ( 2024-12-01)
    Sánchez R.
    ;
    Acosta O.
    ;
    Acosta O.
    ;
    Laymito L.
    ;
    Oscanoa T.
    ;
    Oscanoa T.
    ;
    Oscanoa T.
    ;
    Guevara-Fujita M.
    ;
    Moscol S.
    ;
    Obispo D.
    ;
    Huerta D.
    ;
    Fujita R.
    Background: Tuberculosis (TB) is a highly prevalent chronic infectious disease in developing countries, with Peru being one of the most affected countries in the world. The variants of the N-acetyltransferase 2 (NAT2) gene are related to xenobiotic metabolism and have potential usefulness in TB studies. Aim: To determine whether NAT2 gene variants and acetylator phenotypes are associated with active TB in Peruvian patients. Methods: This study included cases (patients with TB) and controls (population-based data). First, DNA isolation and the rs1799929, rs1799930, and rs1799931 variants of the NAT2 gene were identified using sequencing methods. Subsequently, the acetylator phenotypes, namely slow (SA), intermediate (IA), and rapid acetylation (RA), were also analyzed. Results: The comparison of the frequencies of the rs1799931 variant in the cases and controls revealed significant differences. Risk factors were found for both the A allele (p = 0.00; odds ratio [OR] = 3.04, 95 % confidence interval [CI]: 1.88–4.9) and AG genotype (p = 0.00; OR = 5.94, 95 % CI: 3.17–11.09). In addition, the non-rapid acetylator phenotype (SA + IA) was also found to be a risk factor (p = 0.016; OR = 3.16, 95 % CI: 1.29–7.72). Conclusion: The A allele, GA heterozygous genotype of the rs1799931 variant of the NAT2 gene, and SA + IA acetylator phenotype showed an association with increased risk for the development of TB. In addition to xenobiotic metabolism, other metabolic and immunological functions of NAT2 have also been postulated to confer susceptibility to TB in the Peruvian population owing to its characteristic high Native American component.