Universidad Pedagógica y Tecnológica de Colombia
Recent publications
Chenopodium quinoa Willd. is a species of great interest for global food security because of its ability to adapt to different environmental conditions and its nutritional quality. In Colombia, there are few studies on the genetic diversity of quinoa, and there are no certified seed or registered varieties. Therefore, farmers plant a mixture of genotypes, which is why maximum yield and production are not achieved. The objective of this research was to characterize the genetic diversity in Colombian quinoa crops, for which 30 accessions were evaluated using 27 microsatellite markers. A total of 144 alleles were obtained, with a range of 2–7 alleles per locus (mean = 5.33). The average Polymorphic Information Content (PIC) was 0.60, where QAAT100 (0.80), QAAT112 (0.78), QAAT076 (0.78) and QCA088 (0.77) were the most informative. The expected heterozygosity index (He = 0.69) showed high genetic diversity for the analyzed individuals. Three population groups were detected (K1, K2, K3), whose genetic distances were less than 0.33. The individuals were not grouped according to their geographical origin. The low rates of genetic differentiation in the populations may have been due to the lack of certified seeds, to non-directional selection, and to constant exchange of seeds between farmers in the main producing areas of the Andean region. This study provided preliminary information for the high genetic diversity in Colombian quinoa that can be used for the development of genetic improvement programs for this species.
Background Native potatoes are Andean tubers of great historical, social, food, genetic and nutritional importance, and they contribute significantly to food security by supplementing the household diet and also providing alternative income. Even when their cultivation and consumption imply great benefits, their use and local preservation depend to a large extent on the recognition of their ethnobotanical and cultural importance. In this context, this study consolidates an important ethnobotanical research bases for native potatoes in Colombia. Methods The study collected data through semi-structured interviews and dialogues (130) in the municipality of Chiscas, department of Boyacá, central-eastern Colombia. The questionnaire was focused on native potatoes and sought to investigate the knowledge related to cultivation, diversity, patterns and forms of preparation for use and consumption. Likewise, knowledge heritability mechanisms were investigated and ethnobotanical indices of relative importance, use and culture were estimated. Results Documentation of ethnobotanical knowledge included aspects such as seed care and availability, cultural management of the crop, patterns of use and consumption, as well as ways of preparing the tubers. In total, 23 vernacular names of native potato and 360 reports of use (commercial, domestic or ritual-magical) were recorded for the 15 main genotypes. Quantitative estimates included the importance index: (a) cultural, for which values ranged between 0.059 and 0.812; (b) relative, with records between 0.04 and 0.43; and (c) use, which ranged between 0.06 and 0.63. The ethnobotanical importance index (d) for native potatoes was 57.26, which corresponds to a “very high” ethnobotanical value. This allowed us to identify that Criollas were the most recognized and used potatoes within the community. In addition, it was shown that vertical transmission is the main way in which traditional knowledge about native potatoes is inherited. Finally, an artificial intelligence tool was preliminarily implemented to identify the polarity generated in the interviewees by the questions. Conclusion The results of this research provide valuable information on the ethnobotany of native potatoes in Colombia. The genotypes used by the community of the municipality of Chiscas were recognized for their high gastronomic and nutritional potential, as well as for their great ethnobotanical and cultural importance. These data can be considered as a valuable tool to support any action aimed at the conservation and revaluation of these tubers.
This paper presents a strategy to design ultrawideband power amplifiers with a fractional bandwidth of approximately 200%. It exploits a simple output matching network, which consists of a series transmission line together with a shunt stub, to compensate the output parasitic network of the device. Following this, a multisection transformer is implemented to obtain the optimal load at the intrinsic drain plane. As design examples, several output matching networks were designed for two different size GaN HEMT devices. One of these examples was implemented and characterized, and a drain efficiency from 52% to 70% and an output power between 40 dBm and 42.5 dBm were obtained, over 67% of the 5G sub-6-GHz band (i.e., 0.1 to 4 GHz). The aforementioned results, to the best of the authors’ knowledge, represent the state of the art in broadband power amplifiers.
Cayley hash values are defined by paths of some oriented graphs (quivers) called Cayley graphs, whose vertices and arrows are given by elements of a group H. On the other hand, Brauer messages are obtained by concatenating words associated with multisets constituting some config- urations called Brauer configurations. These configurations define some oriented graphs named Brauer quivers which induce a particular class of bound quiver algebras named Brauer configuration algebras. Elements of multisets in Brauer configurations can be seen as letters of the Brauer messages. This paper proves that each point (x, y) ∈ V = R\{0} × R\{0} has an associated Brauer configuration algebraΛB(x,y) inducedbyaBrauerconfigurationB(x,y).Additionally,theBrauerconfigurationalge- bras associated with points in a subset of the form (⌊(x)⌋, ⌈(x)⌉] × (⌊(y)⌋, ⌈(y)⌉] ⊂ V have the same dimension. We give an analysis of Cayley hash values associated with Brauer messages M(B(x,y)) defined by a semigroup generated by some appropriated matrices A0, A1, A2 ∈ GL(2, R) over a commutative ring R. As an application, we use Brauer messages M(B(x,y)) to construct explicit solutions for systems of linear and nonlinear differential equations of the form X′′(t) + MX(t) = 0 and X′(t) − X2(t)N(t) = N(t) for some suitable square matrices, M and N(t). Python routines to compute Cayley hash values of Brauer messages are also included.
The peels obtained as a byproduct from the processing of fruits (prickly pears) of the Cactaceae family are a rich source of mucilage, a hydrocolloid biopolymer that may have potential application in water/wastewater treatment as a natural coagulant. In this study, the structural (UPLC-QTOF-MS, FTIR, Raman, NMR, XRD, and zeta potential), morphological (SEM), and thermal (DSC/TGA) characterizations of the mucilage extracted from the peels of Opuntia ficus-indica (OFI) fruits were carried out. UPLC-QTOF-MS results revealed the presence of a branched polymer with an average molecular weight of 0.44 KDa for this mucilage in aqua media. The NMR spectra of mucilage in DMSO-d6 indicated that it seemed well-suited as a coagulant with its typical oligosaccharide structure. FTIR studies confirmed the presence of hydroxyl and carboxyl functional groups in the mucilage, indicating its polyelectrolyte nature that could provide coagulating properties through binding and adsorption mechanisms. Likewise, the zeta potential of −23.63 ± 0.55 mV showed an anionic nature of the mucilage. Power XRD technique evidenced the presence of crystalline poly(glycine-β-alanine), glutamic acid, and syn-whewellite. SEM images revealed an irregular and amorphous morphology with cracks, which are suitable characteristics for adsorption mechanisms. The mucilage exhibited two endothermic transitions, with a decomposition temperature in uronic acid of 423.10 ◦C. These findings revealed that mucilage obtained from OFI fruit peels has molecular and physicochemical characteristics that are suited to its possible application as a natural coagulant in water/wastewater treatments.
Coronavirus disease (COVID-19) is an infectious disease caused by SARS-CoV-2. In Colombia, many commercial methods are now available to perform the RT-qPCR assays, and laboratories must evaluate their diagnostic accuracy to ensure reliable results for patients suspected of being positive for COVID-19. The purpose of this study was to compare four commercial RT-qPCR assays with respect to their ability to detect the SARS-CoV2 virus from nasopharyngeal swab samples referred to Laboratorio Carvajal IPS, SAS in Tunja, Boyacá, Colombia. We utilized 152 respiratory tract samples (Nasopharyngeal Swabs) from patients suspected of having SARS-CoV-2. The diagnostic accuracy of GeneFinderTM COVID-19 Plus RealAmp (In Vitro Diagnostics) (GF-TM), One-Step Real-Time RT-PCR (Vitro Master Diagnostica) (O-S RT-qPCR), and the Berlin modified protocol (BM) were assessed using the gold-standard Berlin protocol (Berlin Charité Probe One-Step RT-qPCR Kit, New England Biolabs) (BR) as a reference. Operational characteristics were estimated in terms of sensitivity, specificity, agreement, and predictive values. Using the gold-standard BR as a reference, the sensitivity/specificity of the diagnostic tests was found to be 100%/92.7% for GF-TM, 92.75%/67.47% for O-S RT-qPCR, and 100%/96.39% for the BM protocol. Using BR as a reference, the sensitivity/specificity for the diagnostic tests were found to be 100%/92.7% for the GF-TM assay, 92.72%/67.47% for the O-S RT-qPCR, and 100%/96.39% for BM. Relative to the BR reference protocol, the GF-TM and BM RT-PCR assays obtained similar results (k = 0.92 and k = 0.96, respectively), whereas the results obtained by O-S-RT-qPCR were only moderately similar. We conclude that the GF-TM and BM protocols offer the best sensitivity and specificity, with similar results in comparison to the gold-standard BR protocol. We recommend evaluating the diagnostic accuracy of the OS-RT-qPCR protocol in future studies with a larger number of samples.
The high nutritional potential of native potatoes makes them an invaluable genetic resource for breeding. However, pathogens have caused both yield and industrial quality losses, and plant tissue culture is a promising alternative to obtain clean plant material. We compared distinct segments excised from apical and lateral sprouts taken from tubers as initial explants for in vitro culture of sixteen native potato genotypes. Thus, apical-distal (AD), mid-apical, lateral-distal, and mid-lateral segments were all grown on Murashige & Skoog medium. These explants were aseptic, reactive, and viable for all genotypes (with a probability greater than 30%), yielding cumulative proliferation rates of up to 1:10 individualizable segments, and about 86% of in vitro plants with 2 to 11 roots of up to 117 mm long. Responses were genotype-dependent during all stages of cultivation, and the best responding genotypes were Maravillosa, Duraznillo and Pepina Rodeo. On the other hand, AD sprouts were the best sprout type and segment for in vitro establishment, regardless of genotype. This is the first study of its kind with such a large range of Andean potato genotypes and should contribute to their germplasm conservation and increased multiplication efficiency.
The riffle bugs of the Rhagovelia angustipes complex have presented problems in taxonomy due to high intra-specific variability. Here we identified variation in the complex with morphometric techniques. We analyzed variation of the characters and performed a phylogenetic analysis of a combined matrix of linear measurements, geometric configurations, and discrete characters. We found that characters such as head length, metanotum length, femur width, and the evaluated shape of four characters (head, abdomen, fore tibia, hind femur) were important for the delimitation of species. In particular, we identified the metanotum length as a character that had not been previously considered in the taxonomy of the complex. The phylogenetic reconstruction allowed us to recover some relationships established for the taxonomy of the complex for the salina group, except for the species R. colombiana that was closer to R. calceola and R. calopa. This may be due to a similar natural history, since they share areas of distribution, while the R. bisignata and R. hambletoni groups could not be recovered, showing their low morphological support. In general, the geometric morphometric characters showed high levels of homology, with the head and the anterior tibia being the ones that had the best performance in the tree. Finally, the use of morphometric tools proved to be a powerful input for the taxonomic resolution of species complexes that have problems in their delimitation.
Introduction Early rehospitalisation in mental health units (SMHUs) is when a patient needs to be readmitted in the first 30 days after receiving discharge, and is mainly due to recurrent decompensation of their mental illness. This phenomenon is related to a worse prognosis and has an impact on the family, social and work environment. Absenteeism from work and additional hospital time are expenses for the health and employment system which have made rehospitalisation a phenomenon of special interest. The present study was carried out with the objective of exploring the factors associated with the readmission of patients with psychiatric illnesses treated in two MHUs during 2018, as well as those modifiable factors that act as protection for this condition. Methods Observational, descriptive study with analytical component of cases and controls in two MHUs in different cities of Colombia. Information was obtained by collecting data from the medical records of patients who were admitted between 1 January 2018 and 31 December 2018. The data were collected between 20 February and 27 May 2019. The sample was composed of all the patients who met the criteria for early readmission in both institutions. The study group consisted of 113 patients: (28 cases and 85 controls), matched by by the variables: age, sex, place of hospitalisation and diagnosis. Results In the two hospital MHUs the diagnoses found were: depression (15.5%), bipolar affective disorder (33.1%) and schizophrenia (37.3%). In Bogotá, the most prevalent was depression (31.1%) and, in Tunja, it was schizophrenia (44.8%). For both institutions, the factor most associated with readmission was alcohol consumption, but other variables of treatment, family nucleus, and individual intervention were also associated with a greater probability of early readmission. Conclusions It was possible to demonstrate that the use of atypical and/or depot antipsychotics, hospitalisations longer than 15 days, and prescriptions of less than three drugs at discharge, reduce the number of early readmissions to MHUs.
In this contribution, we extend the concept of coherent pair for two quasi-definite matrix linear functionals u0 and u1. Necessary and sufficient conditions for these functionals to constitute a coherent pair are determined, when one of them satisfies a matrix Pearson-type equation. Moreover, we deduce algebraic properties of the matrix orthogonal polynomials associated with the Sobolev-type inner product〈p,q〉s=〈p,q〉u0+〈p′M1,q′M2〉u1, where M1 and M2 are m×m non-singular matrices and p,q are matrix polynomials.
Immunoglobulin G (IgG) is one of the five antibody classes produced in mammals as part of the humoral responses accountable for protecting the organisms from infection. Its antibody heavy chain constant region is encoded by the Ig heavy-chain gamma gene (IGHG). In humans, there are four IGHG genes which encode the four subclasses, each with a specialized effector function. Although four subclasses of IgG proteins have also been reported in macaques, this does not appear to be the rule for all primates. In Platyrrhini, IgG has been stated to be encoded by a single-copy gene. To date, it remains unknown how the IGHG has expanded or contracted in the primate order; consequently, we have analyzed data from 38 primate genome sequences to identify IGHG genes and describe the evolution of IGHG genes in primate order. IGHG belongs to a multigene family that evolves by the birth–death evolutionary model in primates. Whereas Strepsirrhini and Platyrrhini have a single-copy gene, in Catarrhini, it has expanded to several paralogs in their genomes; some deleted and others pseudogenized. Furthermore, episodic positive selection may have promoted a species-specific IgG effector function. We propose that IgG evolved to reach an optimal number of copies per genome to adapt their humoral immune responses to different environmental conditions. This study has implications for biomedical trials using non-human primates.
The Purpose in Life Test (PIL) is a measure of purpose in life widely used in many cultures and countries; however, cross-cultural assessments are scarce. The present study aimed to evaluate the cross-cultural measurement invariance of the PIL in the general population of seven Latin American countries (Colombia, Ecuador, El Salvador, Mexico, Paraguay, Argentina, and Uruguay). A total of 4306 people participated, selected by non-probabilistic convenience sampling, where Uruguay has the highest mean age (M = 41.8; SD = 16.6 years); while Ecuador has the lowest mean age (M = 24.6; SD = 7.8 years). Furthermore, in each country, there is a higher proportion of women (>60%) than men (<40%). Using Multi-Group Confirmatory Factor Analysis, the factorial structure does not show evidence of invariance among the included countries. However, based on the Multi-Group Factor Analysis Alignment, there is evidence that a three-dimensional structure of the PIL (Meaning of existence, Freedom to make meaning in daily life and Will to find meaning in the face of future challenges) is the same in the participating countries. Results based on item response theory indicate that most PIL items can significantly differentiate responses according to the level of life purpose. In addition, people with low life purpose will tend to choose the lower response alternatives on the PIL; while people with higher life purpose will choose higher response alternatives. The findings indicate that the PIL has the potential to increase knowledge about how people conceive and experience their purpose in life in different countries.
Resumen Introducción Una de las consecuencias del uso prolongado de pantallas luminosas como las del ordenador o las del teléfono móvil es el síndrome visual informático (SVI), donde se presentan síntomas característicos que normalmente desaparecen después de un par de horas de haber dejado de usar los aparatos electrónicos. La prevalencia es alta debido a múltiples factores de riesgo. Objetivo Determinar la prevalencia de SVI en estudiantes de Medicina en tiempos de pandemia. Metodología Estudio observacional descriptivo y de corte transversal. La población a estudio fueron estudiantes de Medicina de la Universidad de Boyacá y los datos fueron recogidos en septiembre y octubre del año 2021 a través de una encuesta electrónica. Resultados Un total de 300 personas participaron en el estudio. El 78% (234) de los estudiantes participantes presentan SVI. El 67,09% (157) de los participantes que refirieron presentar SVI pertenecían al sexo femenino y el 32,91% (77) eran del sexo masculino. Conclusiones El SVI es muy común entre los estudiantes de Medicina de la Universidad de Boyacá. Este estudio ha demostrado que la presencia del SVI se ha asociado significativamente a factores exposicionales que se desencadenaron durante el período de pandemia, en donde las clases virtuales frecuentes y durante horarios prolongados conllevaban a una alta exposición a pantallas. Además, en la era de virtualidad la comunicación mediante redes sociales aumentó el uso de teléfonos móviles, lo cual aumenta la posibilidad de aparición de este síndrome.
Andean blueberry fruit is considered a source of bioactive compounds. However, its industrial applications as an ingredient are limited due to its low stability. In this work, Andean blueberry juice powders were obtained via freeze‐drying. The effects of maltodextrin (MD) and gum Arabic (GA) as encapsulating agents were evaluated on the morphological, physicochemical, and rheological quality of the products, as well as in terms of the recovery of phenolic compounds. All the freeze‐dried powders featured typical macroscopic and microscopic morphology, low moisture content (<5%) and water activity (aw <0.3), high water solubility (>91%), and good flowability. The encapsulation with MD overall favoured higher water activity, solubility, and flowability, and a significant increase of total phenolics recovery in the juice powders, compared to GA or GA:MD mixtures. The results showed that encapsulation by freeze‐drying enables the production of Andean blueberry juice powders with suitable technological characteristics and potential as bioactive ingredients.
Algunas políticas sobre vivienda social en Colombia están destinadas a beneficiar de forma progresiva a familias que posean cierto nivel de protección del Estado. Este trabajo se focalizó en evaluar Viviendas de Interés Prioritario (VIP) incluidas en un proyecto de vivienda implementado en un sector periférico de la ciudad de Tunja-Colombia desde la percepción de los usuarios, proyecto enmarcado en la Ley 1537 de 2012. La metodología tuvo enfoque cuantitativo matizado con elementos del análisis hermenéutico; la información fue recogida por medio de una encuesta a 100 cabezas de familia. La información fue procesada con el software SPSS. Los resultados evidenciaron que los beneficiarios percibieron la VIP como una oportunidad brindada por el gobierno para mejorar su calidad de vida; sin embargo, su diseño y construcción no ha sido óptimo en relación con aspectos físico-ambientales y sociales, requiriéndose implementar mejoras locativas y una mayor inclusión social.
We demonstrate a concept for the giant enhancement of the transverse magneto-optical Kerr effect (TMOKE) using bulk plasmon polariton (BPP) modes in non-magnetic multilayer hyperbolic metamaterials (HMMs). Since the BPP modes are excited through the attenuated total reflection (ATR) mechanism, using a Si-based prism-coupler, we considered a single dielectric magneto-optical (MO) spacer between the prism and the HMM. The working wavelength was estimated, using the effective medium approach for a semi-infinite dielectric-plasmonic multilayer, considering the region where the system exhibits type II HMM dispersion relations. Analytical results, by means of the scattering matrix method (SMM), were used to explain the physical principle behind our concept. Numerical results for giant TMOKE values (close to their maximum theoretical values, ±1) were obtained using the finite element method (FEM), applying the commercial software COMSOL Multiphysics. Our proposal comprises a simple and experimentally feasible structure that enables the study of MO phenomena in HMMs, which may find application in future nanostructured magnetoplasmonic metamaterials for active nanophotonic devices.
The aim of this paper is to present the application of the OWA operator and some of its extensions in the calculation of continent and global tax revenues. The idea is to present how the analysis of an important economic indicator can vary depending on how the information is aggregated. An example was employed based on the Organization for Economic Co-operation and Development (OECD) database using 111 countries that were divided by continent, and then the global tax revenue was calculated using different aggregation operators. Different analyses can be carried out by governments and enterprises to improve decision making and fiscal politics.
Welsh onion (Allium fistulosum) leaves contain several bioactive compounds that can be extracted and used to develop new value-added products (e.g., functional foods and dietary supplements). In the current work, optimal ultrasound-assisted extraction (UAE) conditions to obtain extracts with high polyphenols content and DPPH (1,1-diphenyl-2-picrylhydrazil) scavenging activity were identified using response surface methodology. A complete 3k factorial design was used to evaluate the effect of different variables of the UAE (extraction temperature, time, and ethanol concentration) on the polyphenols content and the DPPH scavenging activity of the extracts. The best conditions for UAE to reach both the highest values of total polyphenols content (51.78 mg GAE/100 g) and DPPH scavenging activity (34.07 mg Trolox equivalents/100 g) were an extraction temperature of 60 °C, time of 10 min, and ethanol concentration of 70% v/v. The antioxidant activity of the extracts obtained at the optimal conditions was also evaluated by 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) and ferric reducing antioxidant power (FRAP) assays obtaining values of 155.51 ± 2.80 μM Trolox/100 g and 1300.21 ± 65.55 μM Trolox/100 g, respectively. Moreover, these extracts were characterized by UHPLC-ESI+-Orbitrap-MS analysis finding that cyanidin (6.0 mg/kg) was the phenolic compound found in the highest amount followed by quercetin-3-glucoside (4.4 mg/kg).
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6,020 members
Efren Munoz
  • Escuela de Química
Cesar Ortiz
  • Escuela de Física
Armando Sarmiento Santos
  • Escuela de Física
Fánor Casierra-Posada
  • Facultad de Ciencias Agropecuarias
Tunja, Colombia
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