La revista Journal of Basic Sciences (antes Revista de Ciencias Básicas UJAT) es una revista electrónica multidisciplinaria, editada por la División Académica de Ciencias Básicas (DACB) de la Universidad Juárez Autónoma de Tabasco (UJAT) desde el 2002. Desde su nacimiento hasta 2014, se editaba semestralmente y de manera impresa, pero durante un proceso de reestructuración y relanzamiento, sufrió algunos cambios. A partir de 2015 cambió de título a su nombre actual, migró al formato electrónico y comenzó a publicarse cuatrimestralmente. La revista publica artículos con resultados de investigaciones científicas originales en los campos de la Física, Química, Matemáticas, Ciencias Computacionales y áreas afines. Sitio web: https://revistajobs.ujat.mx. Editor responsable: Carlos Ernesto Lobato García. Informes: jobs@ujat.mx. Es una revista de Revista de acceso libre.
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Evaluation of Rare Earth Elements in Lacustrine Sediments of the Northern Central Plateau between San Luis Potosí and Zacatecas, Mexico
The Rare Earth Elements consist of Lanthanum to Lutetium and are chemical elements which are less soluble and relatively immobile during geological processes such as low-grade metamorphism, erosion, and hydrothermal alteration. In the San Luis Potosí and Zacatecas states, there are continental type salars which concentrate lacustrine sediments. These sediments are classified as sandy and clay-silt. In this study, the Rare Earth Elements in these sediments were evaluated to identify provenance, depositional environment, and weathering. The lacustrine sediments contain more clay component are slightly enriched in ΣREE. The values normalized to chondrite show an enriched pattern in LREE against HREE and in sediments (NASC). The Negative Eu and Ce anomalies indicate a continental source and a non-oxidative environment, respectively. Meanwhile, the positive Y/Ho ratios indicate the weathering process also suggest a continental affinity
Copyright (c) 2025 JOURNAL OF BASIC SCIENCES https://creativecommons.org/licenses/by-nc-nd/4.0
Condiciones metamórficas del grafito en el Complejo Metamórfico Paleozoico Esquisto Granjeno
El Complejo Metamórfico Paleozoico Esquisto Granjeno se compone por rocas con eductos sedimentarios e ígneos. El énfasis de este trabajo radica en la una unidad grafítica, de la cual no se ha entendido completamente su origen y evolución. Durante el metamorfismo las condiciones de grafitización corresponden a un proceso irreversible. Por lo cual el proceso de grafitización se considera un indicador confiable para estimar las condiciones térmicas máximas durante el metamorfismo. Se realizaron análisis geoquímicos en roca total y mineral con la finalidad de estimar las condiciones de grafitización y la mineralogía formada durante este proceso. Se estima que el proceso de grafitización ocurrió en dos rangos de temperatura de 318–339°C y 426–432°C. Por lo tanto, los sedimentos ricos en materia orgánica depositados en una cuenca oceánica localizada en la periferia del NW Gondwana fueron afectados por alto grado de metamorfismo regional durante el cierre de Pangea.
Grafito, geoquímica, metamorfismo, Complejo Metamórfico Paleozoico Esquisto Granjeno
Copyright (c) 2024 Journal of Basic Sciences
Síntesis de Ugi de tres componentes en presencia de metales de transición. Obtención de N-bencil-2-fenil-2-(fenilamino)acetamida
En este artículo se presenta la síntesis de la N-bencil-2-fenil-2-(fenilamino)acetamida (1) bajo las condiciones de la reacción de Ugi de tres componentes (U-3CR), utilizando nanopartículas metálicas como catalizadores. El producto (1) se obtuvo en rendimiento de 85% bajo las condiciones optimizadas.
-aminoamidas, reacciones multicomponente, reacción de Ugi de tres componentes, nanopartículas metálicas
Contaminación y deficiencia de la calidad por uso de suelos agrícolas: una revisión cualitativa
Tabasco es uno de los estados mayor productor de semillas de “cacao”, esto conlleva a que los suelos presenten contaminación por el desarrollo de actividades agrícolas. Los agroquímicos, contienen metales pesados y ocasionan efectos nocivos para el medio ambiente. Esta es una problemática que han impulsado la búsqueda de alternativas sobre el uso de agroquímicos. El objetivo de esta investigación fue analizar la cultura implementada por el productor, aplicación de agroquímicos, y el conocimiento de medidas de prevención para reducir la presencia de contaminantes, desde un enfoque metodológico cualitativo. Realizamos 2 entrevistas semiestructuradas, la primera dirigida a un productor que usa productos orgánicos y la segunda a uno que trabaja con agroquímicos. Como resultados: los productores usan los agroquímicos con criterios empíricos que conllevan a un inadecuado desempeño de estos productos. La experiencia se constituye en el conocimiento transmitido de generación en generación de la forma de cultivar las tierras.
Bacterias fijadoras de nitrógeno de vida libre provenientes de diferentes rizosferas de mangles
Los microorganismos desempeñan un rol importante en la degradación de petróleo en diversos ecosistemas contaminados; sin embargo, existen organismos resilientes con la capacidad de metabolizarlo. Por lo tanto, se investigan alternativas para remediar estos sitios a través de la biotecnología con el uso de microrganismos. El presente trabajo tuvo como objetivo obtener bacterias fijadoras de nitrógeno de vida libre capaces de degradar petróleo. Los microorganismos se obtuvieron a partir de las rizósferas de mangle: rojo (Rhizophora mangle), blanco (Laguncularia racemosa) y negro (Avicennia germinans), las cuales estaban libres de petróleo. De las tres rizósferas se obtuvieron 16 cepas bacterianas, las cuales se caracterizaron fenotípicamente, y posteriormente se sometieron a crecimiento en Agar Bushnell Hass y triple 17 con petróleo como única fuente de carbono, y determinar si eran petrofílicas. Los resultados demostraron tres especies de cepas bacterianas petrofílicas identificadas como: B1MR, B3MR perteneciente del mangle rojo y B2MN mangle negro.
bacteria, biorremediación, mangles, nitrógeno, petróleo, rizosfera
Regulación de la angiogénesis por antioxidantes en el cáncer de mama triple negativo
El cáncer de mama triple negativo (CMTN) está relacionado con un peor pronóstico y un comportamiento más agresivo. Este subtipo cuenta con una mayor frecuencia de metástasis, la cual se ve favorecida por el proceso vascularización relacionado a la angiogénesis tumoral. El objetivo del estudio fue realizar un análisis de expresión diferencial y ontología de genes (GO) en células MDA-MB-468 en respuesta al tratamiento con el antioxidante CAT-SKL, el análisis se realizó utilizando secuencias públicas contenidas en la base de datos Gene Expression Omnibus (GEO). La angiogénesis fue una de las ontologías que resultó subexpresada (DR) por el tratamiento con CAT-SKL. Los genes proangiogénicos KDR, EGR3, CCN2, S100A7, PDGFRA y FN1 se observaron disminuidos, mientras que el gen antiangiogénico IL18 se mantuvo incrementado. Adicionalmente encontramos que ontologías relacionadas con el transporte de aminoácidos se presentan sobreexpresadas (UR).
Cáncer de mama triple negativo, Angiogénesis, Antioxidante, Tratamiento alternativo
Determinación el parámetro Vs30 en el Municipio de Teapa, Tabasco
Anteriormente, el estado de Tabasco era clasificado como una zona de bajo peligro sísmico, debido a la ausencia de registros de terremotos fuertes. Actualmente, existe la evidencia de que sismicidad en estados aledaños, ha causado daños considerables en la entidad. Uno de los parámetros que permite estimar los efectos que podrían tener los terremotos es la velocidad promedio de las ondas superficiales en los primeros 30 metros del subsuelo (Vs30). Este parámetro fue obtenido en 19 puntos distribuidos en el municipio de Teapa, resultando en velocidades que varían de los 257 a 556 m/s y clasificándose como suelos tipo C y D de acuerdo con NEHRP. Esto pone en evidencia que la región puede estar sujeta a amplificaciones del movimiento del suelo ante la ocurrencia de un terremoto.
Sismicidad de Tabasco, Vs30, efecto de sitio
Problema de control para el modelo básico de la hepatitis C con tratamiento
En este trabajo planteamos y resolvemos numéricamente el problema de control óptimo para el tratamiento con interferón en un enfermo endémico de hepatitis C que responde a la terapia.
Hepatitis C, Control óptimo, Interferón.
Principales alimentos funcionales con efectos hipoglucemiantes en Diabetes mellitus
La diabetes es una alteración del metabolismo que afecta a millones de personas y aumenta el riesgo de muerte. Para controlar esta enfermedad, existen tratamientos farmacológicos y no farmacológicos. Dentro de estos últimos, se incluyen los alimentos funcionales, que son aquellos que tienen beneficios para la salud más allá de su valor nutricional. Estos alimentos pueden ayudar a regular los niveles de glucosa en sangre, que es el principal indicador de la diabetes. Para identificar qué alimentos funcionales son eficaces para la diabetes, se revisaron artículos científicos que evaluaron su efecto sobre la glucosa en ayunas, la glucosa postprandial y la hemoglobina glicosilada (HbA1c). Se encontró que el cacao, café, canela, ajo, guayaba, jengibre, arándanos y cúrcuma son alimentos funcionales que reducen estos parámetros, siendo la guayaba el más efectivo para bajar la glucosa postprandial.
diabetes, alimento funcional, glucosa, glucosa postprandial, HbA1c
Sustainable Replacement of MDF-Melamine Board in Discarded Binary Tables in Higher Education Institutions
The improper management of plastic waste is a global problem due to its slow degradation, which pollutes the ecosystem. Recycling high-density polyethylene (HDPE) is a sustainable solution that reduces carbon emissions compared to the production of new plastic, benefiting both the environment and the economy. This study focuses on the laboratory-scale production of HDPE boards to replace deteriorated MDF-Melamine boards in the División Académica de Ciencias Biológicas (DACBiol) at the Universidad Juárez Autónoma de Tabasco (UJAT). The compression molding process includes eight steps: collection, washing, grinding, melting, molding, pressing, demolding, and finishing. A total of 5.6 kg of HDPE was used to manufacture 16 boards measuring 17x17x1.2 cm, with epoxy resin optionally used for the final finish. The results demonstrate that recycled HDPE is a viable alternative for reducing plastic waste and pollution, offering a practical solution for public and private institutions.
Copyright (c) 2024 Journal of Basic Sciences https://creativecommons.org/licenses/by-nc-sa/4.0
Controlled release kinetics of acetaminophen from carboxymethylcellulose gel
The synthesis of carboxymethylcellulose (CMC) gels was carried out. The gels obtained were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and swelling tests. Once the hydrogels were characterized, the incorporation of the acetaminophen drug was carried out and the amount of active ingredient released by the hydrogel was determined as a function of time by Ultraviolet Visible Spectroscopy (UV-vis). Subsequently, the release of acetaminophen was performed at pH 7 and temperature of 37°C, the swelling tests showed a maximum swelling percentage of 1230 % in a time of 6 h. The results of the release were 0.0.5 % and 0.0.5 % for the hydrogel. The release results were 0.00362 mg/ml in a time of 4 h, reaching a release of 51 mg of acetaminophen/g of CMC hydrogel. In addition, this presented a Fickian type kinetics, since the value is close to 0.5.
Mechanochemical synthesis of Cu-modified zeolite A
Zeolites are crystalline materials with a wide range of applications, the diversity of which is possible due to the properties of these materials. Among their inherent characteristics, it is known that zeolites can be modified with nanoparticles and clusters of other chemical species, which gives them novel properties and allows them to find unusual applications. Therefore, the practical use of these materials can be improved by searching for new modification methods and studying the resulting materials. The objective of this work is to evaluate the results of the mechanochemical modification of zeolite A with copper. Zeolite A was synthesized according to standard methodology and then mixed with copper sulfate and subjected to milling. The original zeolite A and copper-modified zeolite CuA were examined by SEM, UV-Vis, and XRD. Subsequently, the characteristics of both samples were compared and the effect of the mechanochemical attack was studied.
Pectin Extracted from Orange Peel (Citrus Sinensis) to Obtain Bioplastic: Synergistic Effects with Alginate
Pectin, derived from agri-food industry waste, is an almost inexhaustible resource. This study aims to develop a bioplastic from pectin extracted from orange peel, combined with commercial alginate, and to investigate its physicochemical and thermal properties. Pectin was extracted using acid hydrolysis, and its degree of esterification and methoxyl content were determined through titration. The bioplastic film was obtained by ionic cross-linking method. Structural characterization was conducted with Fourier Transform Infrared (FTIR) spectroscopy, while the thermal properties of the pectin and the film were assessed via thermogravimetric analysis (TGA). The results indicated that pectin and alginate exhibited synergistic interactions through miscibility and ionic cross-linking. The bioplastic film demonstrated thermal stability, with a plateau in the range of 130 – 200 °C, indicating that the material possesses suitable properties for thermal processing.
Chemical analysis of the degradation of acid orange 52 using advanced oxidation technologies
The degradation of the acid orange 52 (AN) dye was carried out applying different Advanced Technologies, a cylindrical configuration recirculation reactor were used, the initial concentration of AN is 20 mg/L in 400 mL of solution, the treatment time consisted of 60 minutes, taking samples every 10 minutes and analyzing it by UV-vis spectrometry. The effect of the oxidizing agents used in individual and synergistic systems, the treatment time, the final pH, the generation of CO2 and the change in the coloration of the samples were determined. Efficiencies of up to 99% were obtained when using the O3/1 mL H2O2/UV method and 60 minutes, the final pH was 2.9 attributed to the generation of by-products, 35 mg/L of CO2 were obtained at the end of the process indicating that a percentage of mineralization was reached, finally a 100% decrease in color were observed.
Determination of phthalates in PET-packaged beverages using an MSFIA method coupled with HPLC-DAD
In this work, an online preconcentration method was designed, optimized, and validated using a C18-type membrane with a Multisyrup Flow Injection Analysis (MSFIA) system coupled to HPLC-DAD equipment for the determination of contaminants derived from phthalic acid esters (DMP, DEP, and DBP) in juices stored in PET bottles. The physicochemical and hydrodynamic parameters of the method were optimized using a central composite experiment design. The method showed good precision (˂3%), a LOD of less than 0.5 μg kg–1, and a preconcentration factor of 33 times. After applying the method to 4 samples of juices, concentrations of 172.89 and 100.43 μg kg–1 of DMP and DBP were identified and quantified, respectively. Finally, recovery values that ranged between 44.12% and 141.07% were obtained for the three phthalates.
Evaluation of the microbiological quality of aguamiel and pulque from San Agustín Tlaxiaca, Hidalgo, Mexico
Pulque and aguamiel contain many microorganisms and compounds with prebiotic and probiotic properties that can enhance intestinal microbiota diversity. Despite the potential benefits, their consumption has decreased. This study aimed to evaluate the microbiological quality of aguamiel and pulque from San Agustín Tlaxiaca, Hidalgo. The study examined the presence of aerobic mesophiles, total coliforms, molds, and yeasts. In aguamiel, 1.8x103 CFU/mL of aerobic mesophiles and 6.5 NMP/100mL of total coliforms were found. In pulque, the aerobic mesophiles increased to 1.02x105 CFU/mL, without totals coliforms and 6.43x106 CFU/mL of molds and yeasts. The presence of Gram-bacilli and coccobacilli, molds, and yeasts were observed. Microbiological quality is determined by various factors; however, establishing good practices will allow obtaining pulque with a lower load of unwanted microorganisms.
Implementation of a comic book for teaching molecular symmetry in chemistry
Herein we explore the use of a comic book as didactic material in the teaching of molecular symmetry for organic chemistry students at Juárez Autonomous University of Tabasco. The comic was designed with the purpose of facilitating knowledge acquisition of complicated chemical topics through play-based, simple, creative, and effective learning, to promote meaningful understanding and cognitive strategies. The research was carried out with a mixed approach, and a two-part survey technique was used to collect data. The collected data were tabulated using bar and pie charts for further analysis. In terms of proportions, a significant increase in the number of correct answers was observed after reading the comic book. Specifically, the correct rate increased from 30.6% initially to 55.6% after the intervention with the comic.
Numerical estimation of parameters in mathematical models for pest control
In this work we focused on the estimation of the parameters belonging to a mathematical model for the interaction between three species (plant, plague and bio control agent), with the goal to guaranty the survival of all them. A qualitative analysis of the model is carried out to show the dynamic of it. As well, the model is solved by using a numerical scheme based on multi step method. The obtained code is coupled with the Spux framework to estimate, by stochastic simulations, the unknown parameters of the model. Numerical results show that Spux gives a correct approximation of the parameters because the model simulations with the approximated parameters are in good agreement with the data.
Working memory and performance in demonstrating trigonometric identities: A structural equation model
The learning of trigonometric identities in high school education requires the understanding of the amalgamation of multiple areas such as arithmetic, algebra, and geometry. Additionally, at the neurological level, higher executive functions converge, among which working memory stands out, as it is closely linked to the learning of mathematics in general, this study focuses on trigonometry. This study aims to analyze the influence of higher executive function on the performance of demonstrating trigonometric identities, as well as whether some subcomponents of working memory are influencing this performance. A trigonometric and psychological test was administered to 80 high school students. The data were analyzed through the structural equation model. Among the main results, it is highlighted that there is a direct effect of working memory on one of the components of demonstrating trigonometric identities (Deduction of identities using tangent and secant); additionally, there is a direct effect of a subcomponent of working memory (Alphabetical Ordering) on a component of demonstrating trigonometric identities (Verification of reciprocal identities using sine and cosine). In conclusion, Alphabetical Ordering directly influences language and numerical symbols, which are essential in solving arithmetic problems. Therefore, low ability in this subcomponent is associated with deficient performance in solving these problems, and this may persist in higher grades.
Copyright (c) 2025 Journal of Basic Sciences https://creativecommons.org/licenses/by-nc-nd/4.0
On Riemann-Liouville operators for functions of one and several variables
In this contribution, we present generalizations of path integrals from Multivariable Calculus to develop new fractional total differentials, extending the classical differentials for functions defined on Euclidean spaces. We explore and discuss several examples and key properties of these novel operators. Additionally, we conclude with a comparative analysis of our proposed operators alongside existing ones found in the literature.
Visualization in the building of regular polygons by high school students
It is proposed a possible solution to the lack of knowledge of the characteristics and properties of polygons by high school students. A design is presented of activities in GeoGebra, it´s taken the visualization who a useful ability for the presentation and learning of the polygons and characteristics since diagonals. In addition, levels and phases of the Van Hiele model are used for designing the activities [1]. It was observed the kind of knowledge that the students have, considering the definition of relational and instrumental comprehension given by Skemp in his book “The Psychology of Learning Mathematics”. From the analysis realized we can observe that, although the student’s level ranges between 1 and 2 of the Van Hiele model, the comprehension is not necessarily instrumental.
An unstructured finite-volume method for the two-dimens
In this paper, we present a second-order, time- and space-accurate method for solving conservative transport equation in two-dimensional domains. The spatial discretization is based on a finite volume approach using triangular cells of arbitrary shape. A θ-method is employed for the time integration. A second-order upwind scheme with a Local Extremum Diminishing flux limiter formulation is proposed to approximate the advective terms. The numerical method is validated against classical advection test cases, including different characteristic functions and type of grids. Finally, several tests are conducted to demonstrate the capabilities of the proposed scheme.
Impact of numerical discretization of the total variation noise removal model.
In this manuscript, different numerical discretization techniques are compared, as well as optimization algorithms to find a solution to the total variation based model propoused for Rudin, Osher and Fatemi in 1992. In the same way, we made a qualitative and quantitative analysis of the obtained results.
Evaluation of insulin resistance using the TyG index: pre-pandemic and COVID-19 pandemic comparison
Insulin resistance (IR) is linked to serious complications in COVID-19. Detecting IR is a specialized study not available in basic clinical laboratories. A recent and effective method to assess it is the triglyceride-glucose index (TyG). This study aimed to determine RI using the TyG index in the pre-pandemic (2017-2019) and pandemic periods of COVID-19 (2020-2022) in young university students of the UJAT in the Chontalpa unit. A total of 6318 young people were analyzed, classified by BMI, sex and COVID-19 period. The results of the T&G index indicate the presence of IR in obese subjects of both periods, in men during the pandemic a decrease was observed, although they still present insulin resistance. The incorporation of the T&G index in basic clinical laboratories could facilitate the detection of IR, thus improving the diagnosis, control and treatment of affected patients.
Bayesian inference on the intensity parameter of a mixed Poisson process considering a gamma prior density
In this paper, considering a fixed time interval as the observation period, an inferential study is carried out to estimate the intensity parameter of a mixed Poisson process, under the assumption that the a priori density is gamma. The a posteriori density and Bayes estimators for the intensity parameter are calculated. Similarly, expressions are obtained for the predictive density for a new time between occurrences, the distribution of the number of events that occur in the observation interval and the joint density of the times between occurrences of events.
Efficient and compact methodology for the synthesis of polyurethanes and segmented polyurethane-ureas
Segmented polyurethane-ureas (PUU) are thermoplastic polymers used in tissue engineering due to their biocompatibility, biodegradability, and adjustable mechanical properties. PUU synthesis is carried out using the prepolymer method. In this work, an efficient and compact methodology for PUU synthesis was developed, employing PCL-diol, HMDI, and BDA, optimizing time through rapid drying and controlled synthesis conditions. The results revealed flexible, homogeneous, and semicrystalline material. FTIR analysis confirmed the PUU structure, highlighting the characteristic bands of urethane and urea groups. Thermal analysis (TGA) demonstrated high thermal stability, identifying decomposition stages associated with rigid and soft segments. The proposed methodology significantly reduced the synthesis time, producing materials with structural and thermal properties equivalent to those reported in the literature, positioning it as an efficient alternative for PUU production in biomedical applications.
Feasibility of remediation techniques for hydrocarbon-contaminated soils for application in the state of Tabasco: systematic review
Oil activity in the state of Tabasco has been synonymous with economic opportunity, but in the environmental sphere, it causes negative effects due to significant soil contamination. When this occurs, it is common for some sites to not receive adequate treatment for various reasons, the economic issue being the most relevant. Therefore, the objective of this research was to conduct a search for remediation techniques to determine their feasibility in Tabasco soils. These techniques were obtained from high-quality scientific search platforms such as Google Scholar, Scielo, and Science Direct. For the search, this work was based on some guidelines of the PRISMA protocol for the description of each technique. The search and selection criteria resulted in a total of 10 scientific articles, without distinction, considering whether sophisticated equipment is required, the remediation time, and whether the technique is viable for use in large areas of contamination, thus determining whether they can be applied in Tabasco.
Impact on crops in Veracruz and Tabasco due to oil spills in the last six years
This research analyzed the impact of oil spills on crops in Veracruz and Tabasco, Mexico, from 2017 to 2023. It focused on collecting data from different bibliographic sources, including previous studies and government reports, to identify the causes that caused these spills, such as lack of maintenance, hydrocarbon theft, etc. as well as their consequences on the environment and human health, specifically on the affectation of crops. The study focused mainly on spills that cause damage to crop (corn, coconut, cocoa, among others) and proposes alternatives to minimize future spills and their negative impacts. Finally, this work emphasizes the vulnerability of ecosystems and the population to this type of events.
Added value to agro-industrial waste as an alternative in soil bioremediation
In Agroindustrial waste is byproducts generated by agroindustrial processes and if not processed properly, it represents environmental problems. Various researchers are looking for new avenues and these co-products have added value because there is no clear environmental awareness for their management and final destination, as well as specific legislation. Therefore, this project aims to characterize four agroindustrial wastes from the state of Tabasco: devil fish (Hypostomus plecostomus), banana flour (Musa paradisiaca L), whey, molasses, with the purpose of being implemented in the environmental area: soils, bioaugmentation to microorganisms, means for the production of biosurfactants and thus enhance their value in sustainable practices. The characterizations were based on Official Methods of Analysis of AOAC INTERNATIONAL (OMA) and Official Mexican Standards (NOM-021-SERMANAT-2000, NOM 138-SEMARNAT/SS-2003 and NOM-147-SEMARNAT/SSA1 2007).
Effect of passive control on a cell-converter system
In this work, the system of a boost converter coupled with a solar cell as a power source is studied. The study is approached from the local stability analysis of the three differential equations that model the system. Then the energy shaping control based on passivity is applied to determine the global stability of the system. Using this control, the mathematical model is studied and the simulation results are compared with those obtained experimentally.