Guevara Maldonado, César Byron
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Guevara Maldonado, César Byron
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Quito
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cesarguevara@uti.edu.ec
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56452706300

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Unlocking the puzzle: non-defining mutations in SARS-CoV-2 proteome may affect vaccine effectiveness

2024 , Eugenia Ulzurrun , Ana Grande-Pérez , Daniel del Hoyo , Guevara Maldonado, César Byron , Carmen Gil , Carlos Oscar Sorzano , Nuria E. Campillo

Introduction: SARS-CoV-2 variants are defined by specific genome-wide mutations compared to the Wuhan genome. However, non-clade-defining mutations may also impact protein structure and function, potentially leading to reduced vaccine effectiveness. Our objective is to identify mutations across the entire viral genome rather than focus on individual mutations that may be associated with vaccine failure and to examine the physicochemical properties of the resulting amino acid changes. Materials and methods: Whole-genome consensus sequences of SARS-CoV-2 from COVID-19 patients were retrieved from the GISAID database. Analysis focused on Dataset_1 (7,154 genomes from Italy) and Dataset_2 (8,819 sequences from Spain). Bioinformatic tools identified amino acid changes resulting from codon mutations with frequencies of 10% or higher, and sequences were organized into sets based on identical amino acid combinations. Results: Non-defining mutations in SARS-CoV-2 genomes belonging to clades 21 L (Omicron), 22B/22E (Omicron), 22F/23A (Omicron) and 21J (Delta) were associated with vaccine failure. Four sets of sequences from Dataset_1 were significantly linked to low vaccine coverage: one from clade 21L with mutations L3201F (ORF1a), A27- (S) and G30- (N); two sets shared by clades 22B and 22E with changes A27- (S), I68- (S), R346T (S) and G30- (N); and one set shared by clades 22F and 23A containing changes A27- (S), F486P (S) and G30- (N). Booster doses showed a slight improvement in protection against Omicron clades. Regarding 21J (Delta) two sets of sequences from Dataset_2 exhibited the combination of non-clade mutations P2046L (ORF1a), P2287S (ORF1a), L829I (ORF1b), T95I (S), Y145H (S), R158- (S) and Q9L (N), that was associated with vaccine failure. Discussion: Vaccine coverage associations appear to be influenced by the mutations harbored by marketed vaccines. An analysis of the physicochemical properties of amino acid revealed that primarily hydrophobic and polar amino acid substitutions occurred. Our results suggest that non-defining mutations across the proteome of SARS-CoV-2 variants could affect the extent of protection of the COVID-19 vaccine. In addition, alteration of the physicochemical characteristics of viral amino acids could potentially disrupt protein structure or function or both.

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Surveillance Routing of COVID-19 Infection Spread Using an Intelligent Infectious Diseases Algorithm

2020 , Guevara Maldonado, César Byron , Penas M.S.

In this study, the Intelligent Infectious Diseases Algorithm (IIDA) has been developed to locate the sources of infection and survival rate of coronavirus disease 2019 (COVID-19), in order to propose health care routes for population affected by COVID-19. The main goal of this computational algorithm is to reduce the spread of the virus and decrease the number of infected people. To do so, health care routes are generated according to the priority of certain population groups. The algorithm was applied to New York state data. Based on infection rates and reported deaths, hot spots were determined by applying the kernel density estimation (KDE) to the groups that have been previously obtained using a clustering algorithm together with the elbow method. For each cluster, the survival rate - the key information to prioritize medical care - was determined using the proportional hazards model. Finally, ant colony optimization (ACO) and the traveling salesman problem (TSP) optimization algorithms were applied to identify the optimal route to the closest hospital. The results obtained efficiently covered the points with the highest concentration of COVID-19 cases. In this way, its spread can be prevented and health resources optimized. © 2013 IEEE.

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Development of a Convolutional Neural Network for Detection of Ovarian Cancer Based on Computed Tomography Images

2024 , Gabriela Narvaez-Chunillo , Ronny Ordoñez-Sanchez , Lizbeth Ortiz-Vinueza , Diego Almeida-Galárraga , Fernando Villalba-Meneses , Roberto Bravo-Freire , Andrés Tirado-Espín , Carolina Cadena-Morejón , Paulina Vizcaíno-Imacaña , Guevara Maldonado, César Byron

Ovarian cancer is one of the most frequent gynecologic malignancies in women, but it is often detected in late stage, leaving patients with little time to follow a successful therapy. Specialists have opted to use computer-aided diagnosis (CAD) for the detection of ovarian cancer through the analysis of computed tomography (CT) images, in which the professional examines the size, shape and different characteristics that enable a precise diagnosis in the ovary. This present project purposes a Convolutional Neural Network (CNN) which consist on four convolutional layers; including two pooling layer and two fully-connected layer. The cancerous ovaries images is selected from the Cancer Imaging Achive dataset for training and validation of the model. Moreover, the training of the CNN contain filters to ensure that all of the images are the same dimensions and pixel size. The testing results from the training of the images showed that the proposed model obtained a range of accuracy that goes from 90.0% to the best of the cases 98.85%. The variables obtained like the data of the pressure and loss of the training were compared with those of the validation, allowing for the determination of a successful CNN training.

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Development of an accessible video game to improve the understanding of the test of honey-alonso

2020 , Salvador-Ullauri, L. , Acosta-Vargas, P. , Jadán Guerrero, Janio , Guevara Maldonado, César Byron , Sanchez-Gordon, S. , Calle-Jimenez, T. , Lara Álvarez, Patricio

When evaluating the learning styles of several individuals using the Honey-Alonso test, some users did not understand the meaning of several of the questions. This may be due to problems of context, tiredness in front of the extension of the test, lack of understanding or disinterest. The Honey-Alonso test consists of four groups of twenty questions each. Each group of questions allows identifying the level that an individual possesses on each one of the four learning styles. These styles are: active, reflective, theoretical and pragmatic. Answering a questionnaire of eighty questions is not an easy task from an andragogical point of view. This article proposes the creation of an educational video game designed with a script based on the questions of the Honey-Alonso test. The answers selected by the player are taken as a condition to determine the order of the next questions presented to the player. © Springer Nature Switzerland AG 2020.

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Effect of Burnout Syndrome on work performance in administrative personnel

2024 , Verónica Adriana Freire Palacios , Sridam David Arévalo Lara , María Belén Espíndola Lara , Andrea Ramírez Casco , David Miguel Larrea Luzuriaga , Guevara Maldonado, César Byron

Burnout syndrome can negatively affect workers' performance. Objective: To determine the prevalence of Burnout Syndrome and its impact on the Administrative Performance of the Human Talent at the Chimborazo Sports Federation. This study is quantitative, descriptive, and cross-sectional, involving 21 administrative workers. The Maslach Burnout Inventory Questionnaire was used to measure burnout, and a Job Performance Questionnaire was applied. Descriptive and correlational analyses were conducted. Results showed that 10 % had high levels of burnout, 14 % medium, and 76 % low. The most affected dimensions were personal accomplishment and depersonalization. Job performance was mostly regular (90 %). A significant correlation was found between burnout and job performance (r=0,689, p=0,001). Burnout explained 41,7 % of the variability in performance. Conclusions: There is an inverse relationship between burnout syndrome and job performance in this group of workers. Preventive measures are recommended.

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Artificial Intelligence in Higher Education: A Predictive Model for Academic Performance

2023 , Pacheco-Mendoza S. , Guevara Maldonado, César Byron , Mayorga-Albán A. , Fernández-Escobar J.

This research work evaluates the use of artificial intelligence and its impact on student’s academic performance at the University of Guayaquil (UG). The objective was to design and implement a predictive model to predict academic performance to anticipate student performance. This research presents a quantitative, non-experimental, projective, and predictive approach. A questionnaire was developed with the factors involved in academic performance, and the criterion of expert judgment was used to validate the questionnaire. The questionnaire and the Google Forms platform were used for data collection. In total, 1100 copies of the questionnaire were distributed, and 1012 responses were received, representing a response rate of 92%. The prediction model was designed in Gretl software, and the model fit was performed considering the mean square error (0.26), the mean absolute error (0.16), and a coefficient of determination of 0.9075. The results show the statistical significance of age, hours, days, and AI-based tools or applications, presenting p-values < 0.001 and positive coefficients close to zero, demonstrating a significant and direct effect on students’ academic performance. It was concluded that it is possible to implement a predictive model with theoretical support to adapt the variables based on artificial intelligence, thus generating an artificial intelligence-based mode. © 2023 by the authors.

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Editorial design of interactive picture book with mobile application based on uxd user experience design

2020 , Borja Galeas, Carlos , Guevara Maldonado, César Byron , Amagua M.

This research presents an interactive human-computer learning system model applying adaptive editorial design. The proposal aims to generate an interactive picture book and a mobile application based on user experience design (UxD). The results will be obtained using UX metrics and will have the particularity of working with the technique of participatory design and reticular deconstruction. This book includes its presentation as an audiobook and an editorial composition with pop-ups and pages to paint. © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG 2020.

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Autonomous Learning Mediated by Digital Technology Processes in Higher Education: A Systematic Review

2020 , Fierro-Saltos W. , Sanz C. , Zangara A. , Guevara Maldonado, César Byron , Arias Flores, Hugo Patricio , Castillo Salazar, David Ricardo , Varela Aldas, José , Borja Galeas, Carlos , Rivera R. , Hidalgo-Guijarro J. , Yandún-Velasteguí M.

The concept of autonomous learning has been resignified in recent years as a result of the expansion of the different types of study. Online education in higher education institutions has become an effective option to increase and diversify opportunities for access and learning, however, high rates of dropout, reprisal and low averages still persist. academic performance. Recent research shows that the problem is accentuated because most students have difficulty self-regulating their own learning process autonomously. From this perspective, the purpose of the study was to examine and analyze, through a systematic review of the literature, on autonomous/self-regulated learning, theoretical models and determine which variables influence a learning process mediated by technology processes in the higher education. The findings indicate that: (1) autonomous learning is a synonym of self-regulation; (2) Pintrich’s self-regulatory model is the most used in digital contexts; and (3) the self-regulatory variables identified are wide and varied. © Springer Nature Switzerland AG 2020.

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Health Impact of Gnathostomiasis and its Integral Approach to Parasitic Infection: A Systematic Review

2024 , Gisnella María Cedeño Cajas , José Andrés Zaporta Ramos , Andrea Stefannia Flores Villacrés , Guevara Maldonado, César Byron

The present study focuses on gnathostomiasis, a parasitic disease caused by the nematode gnathostoma that affects both humans and other animals, with a prevalence of 0,14 %. The aim of the study is to analyze the main research related to gnathostomiasis, its diagnosis and treatment. To achieve this objective, a systematic review of clinical cases, observational and retrospective studies of the disease was carried out, following the PRISMA methodology. The literature search, conducted between 2018 and 2022 in the Web of Science, Scopus, PubMed, Redalyc and Dialnet databases, resulted in the identification of five articles relevant and pertinent to the topic. The study findings indicate that gnathostomiasis, on the rise in Latin America and Asia, is transmitted mainly through the consumption of raw fish infected with Gnathostoma larvae. Although preventive measures and treatments, such as albendazole, are available, their efficacy is limited, and it is difficult to implement changes in dietary habits. Therefore, more research is needed to better understand the disease, develop more effective diagnostics and treatments, and raise awareness among physicians of its increasing global prevalence.

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The triple helix model linked to knowledge transfer and economic progress from universities [El modelo de la triple hélice vinculado a la transferencia de conocimiento y progreso económico desde las universidades]

2023 , Bonilla-Jurado, Diego , Guevara Maldonado, César Byron , Montero I.K.S. , Pazmiño S.J.I. , Zuta M.E.C.

The strategic actions that are being developed from the Ecuadorian universities, are heading towards the linking of innovative factors under an interrelated scheme known as Triple Helix, whose intention is framed in connecting entrepreneurship, using knowledge and society as a platform, generating a model sustainable development between university-state-business. The objective of this research is to show the relationship between university-company-state with entrepreneurial research through the triple helix functional model, with a view to innovative potentializing that serves as a boost to socioeconomic progress. The research approach is qualitative at a descriptive level, using a hermeneutical review focused on entrepreneurship studies, business and university alliances, government plans and the triple helix theory. The results indicate that scientific research based on the triple helix method should be strengthened, the main obstacles being lack of communication, business disinterest and distorted state policies. The Ecuadorian universities UEM, UTB and UEB must make concerted efforts so that the investigations are directed towards the true social needs of each area. The conclusions indicate that the links of the triple helix model lead to socioeconomic strengthening through the development of research and scientific projects, without neglecting technological advances. © Este es un artículo en acceso abierto.

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