Pedagogical and Technological University of Colombia
Recent publications
This review summarizes how salinity and temperature, two key global factors driven by climate change in freshwater systems, interact with other stressors on organisms in controlled small-scale factorial experiments at the population, individual, or subindividual level (excluding mesocosm and field studies). Despite the growing interest, research following all these criteria remains limited with 156 publications of which 50% analyzed stressors + salinity, 46% stressors + temperature, and only 4% involved the triple combination. Research on the combined effect of temperature and salinity predominantly focused on metals, pesticides, and, to a lesser extent, emergent contaminants, such as microplastics and nanomaterials, encompassing various biological models and responses. In general, increased temperature amplifies the single effect of stressors, whereas salinity leads to a higher diversity of responses, with similar proportions of synergisms and antagonisms. Fish (Salmoniformes, Perciformes, and Cypriniformes) were the most studied organisms. Among Crustacea, only cladocerans of the genera Daphnia and Ceriodpahnia were considered. The present review highlights the need to include other species that play key roles in freshwater food webs and to increase triple combination studies to understand complex interactions and develop adaptation and mitigation strategies to preserve the environment and its services in this changing world. Graphical Abstract
Este artículo reflexiona sobre la incorporación de la educación para la ciudadanía global (ECG) en la enseñanza del idioma inglés (ELT, por sus siglas en inglés) en educación media, conside­rando las percepciones de los docentes de inglés. Mediante una revisión de literatura especializada y del análisis de las percepciones y prácticas docentes se conceptualiza la ECG y la ELT y sus inter­relaciones y se proponen aspectos para su implementación efectiva. Se encuentra que ambos campos tienen potenciales sinergias por el carácter global del inglés; sin embargo, en la práctica, el enfoque sigue en contenidos gramaticales, no en temas significativos para los jóvenes, razón por la que se proponen aspectos para incorporar la ECG en la ELT. Se concluye que se requieren mayores esfuerzos para replantear programas de estudio, transformar prácticas educativas e investigar esta integración en contextos particulares, de modo que se aproveche mejor el potencial de la ciudadanía global para una educación integral del inglés en la educación media.
Quinoa is a pseudocereal of great importance because of its nutritional content, great adaptability and broad genetic variability. In Colombia, genetic studies on quinoa are scarce, and there are no certified varieties. Rather, varietal mixtures that affect grain quality and, therefore, postharvest and marketing processes grow in the field. The objective of this study was to carry out a morphoagronomic characterization of five quinoa cultivars under field and greenhouse conditions in Tunja-Boyacá using 21 qualitative and quantitative descriptors, estimating their variation with descriptive, multivariate, and cluster analyses. The results show a high phenotypic segregation among cultivars, where yield, diameter, and panicle length were the quantitative variables with greater variation both in the field and in the greenhouse. The multivariate analysis showed that 72.54% of the variance observed in the greenhouse and 75.20% in the field were explained by the first two components, where plant height, stem diameter, panicle density and color, and stem color were discriminating variables. In the field and in the greenhouse, three groups of cultivars were formed according to the yield and desirable morphoagronomic characteristics. Finally, under the present environmental conditions, the more promising quinoa materials for a breeding program were Blanca Subachoque and Tunkahuan. Keywords: Chenopodium quinoa; andean culture; morphoagronomic descriptors; phenotypic variation; pseudocereal; yield
Single‐photon emitters are essential components for the development of optical quantum computing and other quantum technologies, and semiconductor quantum dots are one of the most promising systems for scalable implementation of this type of light sources. However, polarization decoherence is still an important challenge to overcome. Herein, the combined influence of the electron–hole exchange and the Förster energy transfer in a pair of laterally coupled self‐assembled quantum dots, on the exciton‐spin coherence time, is studied. The numerical simulations suggest that under some conditions, the interplay between those two interactions slows the exciton‐spin decoherence as compared to the single‐dot case, which favors the applicability of quantum dots in quantum light generation devices.
In this article, we are going to discuss about how alternant codes over Eisenstein integers are crucial in today’s technologies especially in encoding data and correction of those data. Based on the parity check matrices of alternant codes, the codes are constructed with symbols from finite commutative local rings with unity of Eisenstein integers modulo n. Particularly, the factorization of xn1x^{n} - 1 is over the unit-ring of an appropriate extension of the finite local commutative ring of Eisenstein integers. These codes are built similarly to the BCH codes over the finite integer rings and provide a solid background for the process of encoding the data. This work further proved the applicability of the said algorithm for the purpose of error correction in the discussed alternant codes in order to improve transference effectiveness. Through analyzing the mathematical concepts behind as well as practical applications of alternant codes over Eisenstein integers the possibility of changing today’s technological setting is disclosed. The paper demonstrates that the purpose of the codes is to enhance data integrity and security and underlines that this is why they should be useful for modern communication systems and much more.
Amazon parrots stand out as one of the most illegally traded Psittacids in the neotropics. However, the lack of effective tools for determining the geographical origin of confiscated individuals has impeded the development of well-informed release programmes. In this study, we evaluated the efficacy of the cytochrome oxidase subunit I (COI) gene to identify phylogeographical groups and infer the origins of seized individuals across six Amazon parrot species.
The challenge of bone tissue regeneration implies the use of new advanced technologies for the manufacture of polymeric matrices, with 3D printing technology being a suitable option for tissue engineering due to its low processing cost, its simple operation and the wide use of biomaterials in biomedicine. Among the biopolymers used to obtain porous scaffolds, poly(lactic acid) (PLA) stands out due its mechanical and biodegradability properties, although its low bioactivity to promote bone regeneration is a great challenge. In this research, a 3D scaffold based on PLA reinforced with bioceramics such as graphene oxide (GO) and β-tricalcium phosphate (TCP) was designed and characterized by FTIR, XRD, DSC, SEM and mechanical tests. The in vitro biocompatibility, viability, and cell proliferation of the poly-l-lysine (POLYL) functionalized scaffold were investigated using Wharton Jelly mesenchymal stem cells (hWJ-MSCs) and confirmed by XPS. The incorporation of GO/TCP bioceramics into the PLA polymer matrix increased the mechanical strength and provided a thermal barrier during the fusion treatments that the polymeric material undergoes during its manufacturing. The results show that the functionalization of the scaffold with POLYL allows improving the cell adhesion, proliferation and differentiation of hWJ-MSCs. The resulting scaffold PLA/GO/TCP/POLYL exhibits enhanced structural integrity and osteogenic cues, rendering it a promising candidate for biomedical applications.
Silylation is a widely used derivatization technique for the gas chromatographic analysis of benzodiazepines, a class of psychoactive drugs commonly encountered in forensic and biological samples. This study investigated the optimal experimental conditions for the silylation of benzodiazepines using N,O-bis(trimethylsilyl)trifluoroacetamide containing 1% trimethylchlorosilane (BSTFA + 1% TMCS), a widely employed silylating agent. Ten structurally different benzodiazepines, including variations within the classic 1,4-benzodiazepine core and triazolo ring derivatives, were selected to address the effect of structural diversity on silylation. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used to optimize the silylation of benzodiazepines by means of GC-MS analysis. PCA identified key experimental factors influencing silylation efficiency and distinct response patterns of different benzodiazepines. HCA further categorized the benzodiazepines based on their silylation behavior, highlighting the need for tailored derivatization strategies. The results indicated that the BSTFA + 1% TMCS concentration and solvent volume were pivotal for achieving high silylation efficiency, whereas the temperature, reaction time, and catalyst were less critical. The optimized method was successfully applied to 30 real forensic samples, demonstrating its efficacy in detecting and identifying various benzodiazepines, including designer drugs like etizolam. This study provides a foundation for improving drug detection methodologies in forensic toxicology and provides useful insights into the dynamics of benzodiazepine silylation and the use of individualized analysis parameters.
This paper presents a contribution to the state of the art in the design of tactile sensing algorithms that take advantage of the characteristics of generalized sparse matrix-vector multiplication to reduce the area, power consumption, and data storage required for real-time hardware implementation. This work also addresses the challenge of implementing the hardware to execute multiaxial contact-force estimation algorithms from a normal stress tactile sensor array on a field-programmable gate-array development platform, employing a high-level description approach. This paper describes the hardware implementation of the proposed sparse algorithm and that of an algorithm previously reported in the literature, comparing the results of both hardware implementations with the software results already validated. The calculation of force vectors on the proposed hardware required an average time of 58.68 ms, with an estimation error of 12.6% for normal forces and 7.7% for tangential forces on a 10 × 10 taxel tactile sensor array. Some advantages of the developed hardware are that it does not require additional memory elements, achieves a 4× reduction in processing elements compared to a non-sparse implementation, and meets the requirements of being generalizable, scalable, and efficient, allowing an expansion of the applications of normal stress sensors in low-power tactile systems.
The scoping review aimed to analyze the current methods of measuring working memory (WM) in healthy older adults (60–85 years) without cognitive impairments. The primary objective was to identify common methodological limitations and understand their implications for reliability, ecological validity, and the potential for transferring WM measures to everyday tasks. The hypothesis centered on the inconsistency and limited applicability of WM measures in real-world contexts. The review included 30 empirical studies selected using PRISMA guidelines, focusing on studies published post-2018 across multiple databases, emphasizing WM evaluation in aging. The main findings revealed notable heterogeneity in measurement tasks, with studies using varied tests (e.g., N-Back, Digit Span) and reporting limited use of response time as a measure. A geographic analysis showed that most studies originated in the U.S. and Europe. A significant proportion of the studies lacked reliability parameters, limiting their applicability in everyday contexts. The discussion highlighted theoretical differences as a contributing factor to measurement inconsistencies and emphasized the need for ecological approaches. Future research should address the observed bias, methodological limitations, and explore reliable, transferable WM measures for older adults.
Resumen Como resultado de la vivencia académica experimentada en el posdoctorado, surge este texto de provocación desde la escritura como ensayo. A partir del lugar de la palabra se construyen espacios de pensamiento que provienen de varios incómodos. El primero de ellos, ¿Cómo asumimos las investigaciones?, muchas veces practicada desde sistemas de relaciones inconexas, transitándolas quizás desde el sentido común, así, ésta se vuelva repetitiva, sin respiro, sin vida. Con ello, accionar otras maneras de habitarlas −a través de la afirmación del acto de investigar, efecto de la composición de una política de relaciones, por la cual la investigadora, la investigación, los intercesores y el camino mismo se encuentran en un espacio-tiempo de invención. Por eso, este texto está escrito para cuestionar la investigación, la vida y lo que ella puede. En ese camino, la propuesta está dividida en tres actos: el primero, donde se hablará de aquellas posturas investigativas que pueden asumir verdades y sus formas impuestas, un segundo, se cuestionará: ¿Será posible que las investigaciones en educación matemática provoquen delirios?, el tercer y último momento, problematizar un afirmar la vida desde lo ético-estético-político para que se pueda pensar desde lo posible, posturas investigativas contemporáneas otras.
In this work, we present the preparation of a hybrid material constituted by a Metal-Organic Framework (type MIL-101(Fe)) and a natural clay ceramic monolith (NCCM), the materials were successfully assembled through an in-situ hydrothermal method. The composites were characterized by powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), N2 adsorption-desorption isotherms at 77 K and CO2 adsorption at 273 K; these techniques confirmed the obtaining of the hybrid material and, in addition, through studies before and after adsorption mechanisms involved were identified. Then, the As(V) adsorption capacity of the materials was evaluated using an aqueous arsenic solution; from which high adsorption capacities of up to 268 mg g− 1 and 61.5 mg g− 1, respectively. In addition, kinetic and equilibrium studies of As(V) adsorption were carried out. Finally, the potential capacities of the hybrid material consisting of Al2O3, AlO6-SiO4 and Fe3O4 for the adsorption of H3AsO4, were studied through density functional theory calculations. Supplementary Information The online version contains supplementary material available at 10.1038/s41598-024-80400-7.
In this research, we compared thermochronological and traditional one-dimensional thermal models across the Middle Magdalena Valley (MMV), Eastern Cordillera, and Eastern Llanos Basins in Colombia. These models allow us to relate cooling/heating histories to exhumation events, subsidence, fault activities, and fluid flow. The Eastern Cordillera and Eastern Llanos Basins are discriminated as prospective zones for hydrocarbon (HC) generation. The De Armas Syncline at the MMV basin shows high thermal maturity (127°C), describing rocks completely depleted in terms of HC generation. The eastern zone of this syncline is buried until it reaches temperatures above 150°C. The contrast between thermal models in the Eastern Cordillera basin suggests a possible sediment supply scenario from the west to the east of the Soapaga Fault. In the Eastern Llanos basin, the thermal histories between both models explain the latest uplift and sediment supply processes from the hinterland zone of the Eastern Cordillera to the foothill zone of the Eastern Llanos basin. In terms of thermal evolution, the three basins are different, reaching different levels of burial and HC maturity. However, in terms of cooling events related to exhumation, the basins have similarities as they are controlled by the mountain building of the Eastern Cordillera of Colombia.
Background/Objectives: Studies focused on the soccer goalkeeper position in training and official matches are scarce. The present study aimed to analyze the external load during training sessions and official matches in semi-professional goalkeepers. Methods: Data from goalkeepers (n = 6) from the youth ranks of a professional team belonging to the first Spanish soccer league have been used. The sample is made up of a total of 758 data collected during all the training and competitions carried out by the analyzed teams that made up the squad during the 2021/2022 and 2022/2023 seasons. A descriptive and inferential analysis was carried out based on the category (Youth B or Youth C) and the sports context (training or competition). Results: The results showed significant differences depending on the category (average time to feet left, average time to feet right, total jumps, total dives, total left dives, total right dives, high metabolic load distance (HMLD), and high metabolic power efforts (HMPE)), and the sport context (average time to feet right, total jumps, total dives, total left dives, total right dives, total distance, distance 18–21 km/h, distance 21–24 km/h, Dec 2–3, efforts, and HMLD). Conclusions: The EL of the GKs shows differences regarding the category and the context. Therefore, it is necessary to analyze and determine the threshold of each player considering different variables related to the external and internal load to individualize the training tasks and prevent injuries due to overload.
Currently, research on composite materials derived from natural fibers and agro-industrial waste has generated industrial proposals for producing useful materials with sufficient mechanical strength for applications involving the reuse of waste for secondary purposes. The objective of this study was to determine the influence of fiber content on the final tensile strength of the composite material, serving as a reference for the manufacture of plates. To achieve this, high-density polyethylene (HDPE) composites reinforced with short banana fibers were prepared using a blade mill and hot compression molding techniques. Two levels of short banana fiber content—10% and 20% by weight—were used, along with two types of HDPE: virgin and recycled. We evaluated the effect of adding short banana fibers on the mechanical properties of the composite, specifically tensile strength, according to the ASTM D638 standard for polymeric materials. These results were correlated with the structural properties obtained through morphological, chemical, and thermal characterization of the developed materials. The mechanical evaluation results showed that the tensile strength and elastic modulus depend on the short banana fiber content and the type of high-density polyethylene. Thermogravimetric analysis revealed that the composites decompose faster than the pure polymers (virgin and recycled HDPE). Based on these findings, the composite material prepared under optimal conditions is recommended for use in walls or construction boards where high tensile strength is not critical, due to the decreased mechanical properties resulting from the incorporation of agro-industrial waste.
The axial Arcabuco-Floresta segment of the Eastern Cordillera basin, Colombia exhibits a complex geological history characterized by both along and across strike variations in deformation and exhumation, as well as magmatic activity, all of which provide valuable insights into the broader tectono-thermal evolution of the Andean region. In this study, we combine existing thermochronological data, with 16 new zircons (U-Th)/He and 9 new fission-track dates, and numerical modeling to investigate the thermal history in response to such anomalies across the axial Arcabuco-Floresta segment. Single grain ZHe data from Devonian to Lower Cretaceous strata range from 74 to 20 Ma. ZFT data from the same samples show a broader age distribution ranging from 200 to 70 Ma. The integration of different inverse modeling approaches suggests that cooling, here interpreted as exhumation, occurred in three distinct episodes which can each be linked to different regional tectonic interactions since the Late Cretaceous. Over this time, exhumation commenced in the northern and western parts of the basin and extended progressively through to the eastern and southern parts. The first episode, from the Late Cretaceous to Eocene is related to the accretion of different oceanic terranes related to Farallon Plate. The second, from the Oligocene to Middle Miocene, is interpreted as a probable compressional response to accretion of the Panamá-Chocó Arc, Nazca Plate and the Gorgona Terrane. The third, extending from the Middle Miocene to Pleistocene, may be associated with exhumation driven by far-field deformation resulting from the final collision phase of the Panamá-Chocó block with South America and its interaction with the Nazca and Caribbean plates. This last phase led to the complete emergence of the Eastern Cordillera and its development as an orographic barrier. No evidence was found suggesting any possible influence of thermal overprinting on the thermochronological data in the basin.
Recent initiatives have highlighted the need for integrating a gender perspective into English Language teaching (ELT), particularly in Colombia where gender diversity in education lacks significant sociocultural advancement. This study investigates the perceptions of 11 queer preservice English‐language teachers (PSELTs) from a Colombian public university, using semistructured interviews to explore their views on queering ELT and their future roles as educators. The findings emphasise the importance and challenges of adopting a queer perspective in ELT, essential for creating inclusive environments that respect (queer) students' identities. Moreover, the experiences of these PSELTs during their training have empowered and motivated them as future educators to advocate for societal transformation by promoting awareness of gender diversity in Colombian EFL classrooms. This study supports critical educational reforms that recognise and integrate diverse identities, enriching teaching practices and fostering inclusive learning environments.
The Cooper-pair distribution function Dcp(ω,Tc) of Untwisted-Misaligned Bilayer Graphene (UMBLG) in the presence of an external electric field is calculated and analysed within the framework of first-principle calculations. A bilayer graphene structure is proposed using a structural geometric approximation, enabling the simulation of a structure rotated at a small angle, avoiding a supercell calculation. The Dcp(ω,Tc) function of UMBLG indicates the presence of the superconducting state for specific structural configurations, which is consistent with the superconductivity in Twisted Bilayer Graphene (TBLG) reported in the literature. The Dcp(ω,Tc) function of UMBLG suggests that Cooper-pairs are possible in the low-frequency vibration region. Furthermore, the structural geometric approximation allowed the evaluation of the effect of the electric field on the superconducting state of UMBLG and its superconducting critical temperature through the Ncp parameter.
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