66 research outputs found

    Elementos para contribuir con el empoderamiento de la democracia en Colombia

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    Da cuenta del trabajo que realizó el grupo de investigación «Filosofía, Sociedad,Educación», de la Universidad Pedagógica y Tecnológica de Colombia (UPTC)con el fin de responder a la pregunta: ¿De qué forma se puede contribuir con elempoderamiento de la democracia en Colombia? El método que aplicó lainvestigación fue el cuantitativo e interpretativo, porque permitió, a partir deencuestas realizadas por el Observatorio Político de la Universidad de los Andes,el Barómetro de las Américas y el grupo de investigación, conocer, comprendery analizar la percepción ciudadana de la democracia en Colombia. Este criteriose constituyó en la fundamentación teórica con la cual se propuso, a través del pensamiento filosófico, que uno de los elementos fundamentales para mejorarla democracia es implementar una reforma educativa que garantice una educacióncon calidad filosófica, ética y política de los ciudadanos para recuperar y validarla esfera pública

    El Paisaje de la Ruta Libertadora en Boyacá como Patrimonio cultural

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    En el presente artículo se revisa el tema del valor del paisaje como patrimonio cultural en el territorio comprendido por la Ruta Libertadora en Boyacá. La presentación comprende la aproximación a experiencias que han visto en el paisaje un patrimonio cultural mundial o local. Al considerar distintos lugares se tienen en cuenta los procesos de recuperación, salvaguardia o protección desarrollados mediante mecanismos o lineamientos potenciados por organismos como la Unesco y los Ministerios o entidades de cada país. En el caso colombiano, desde el Ministerio de Cultura se han definido políticas apoyadas en la ley que paulatinamente han avanzado en el cumplimiento de metas con el respaldo de los entes departamentales públicos y privados.  La revisión de experiencias confiere un panorama sobre la gestión llevada a cabo en el propósito de lograr el reconocimiento del paisaje en su dimensión de patrimonio cultural de las naciones. Tal valoración resulta pertinente en el proyecto que busca resignificar patrimonialmente la Ruta Libertadora, pues permitiría establecer una metodología facilitadora en la construcción de un modelo cuya aplicación conlleve a encontrar sentidos actuales a este contexto histórico, con base en un enfoque definido por el arraigo y la pertinencia

    “Zombie attack” a new way to teach Chemistry

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    The Higher Education requires new models which allow training people able to adapt and survive in changing environments. It is based on the use of technologies and the adaptation of knowledge to people. It is about an education according to circumstances, which is adapted to context and virtual behaviour of people. One of the main difficulties that lecturers find in the classroom is how to maintain students' attention and interest in their subject, especially when students also think that the subject is not important for their training. In order to motivate these students, innovation in educational techniques and methodologies, such as experiential learning, are progressively being imposed to and/or coordinated with the traditional ones. Escape Room is a very modern concept in education, based on the development of mental skills for the solution of enigmas and problems. It is a tool to develop the cooperative, cognitive, deductive and logical reasoning skills of the students. In this work, an educational gamification experience based on the escape room concept is presented. The students have 1 hour and 30 minutes to carry out this activity. They will have to solve four puzzles and enigmas that will give them the key to open a treasure chest and finally let them escape from the classroom. Logic, ingenuity and teamwork will allow participants to develop not only chemical competence, but also other basic skills. The story that is told throughout the escape room is a zombie attack: the city has been infected (with a virus) and only the occupants of the room where the activity takes place have not been infected. In addition, they can all protect themselves if they are able to open the chest where the antidote is located. The aim of this activity is to enhance the knowledge acquired throughout the semester as well as the development of skills.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

    Rapid Magnetic Dispersive solid phase extraction to preconcentration/determination of Cd and Pb in aqueous samples

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    A new magnetic dispersive solid phase extraction (MDSPE) method and graphite furnace atomic absorption spectrometry (GFAAS) have been combined for the analysis of Cd and Pb in environmental samples. For the preconcentration, a shell structured Fe3O4@graphene oxide nanospheres was synthetized and characterized. The material was suspended in the ionic liquid 1-n-butyl-3-metilimidazolium tetrafluoroborate [BMIM][BF4], the obtained stable colloidal suspension is named ferrofluid. GO presents excellent adsorbent properties for organic species due to the presence of the electronic π system. For this reason, the organic ligand [1,5-bis-(2-dipyridyl) methylene] thiocarbonohydrazide (DPTH) was used in order to form organic complexes of Cd and Pb. Once the DPTH ligand has been added to sample, the ferrofluid was injected and finely dispersed in the sample solution in order to extract the formed chelates. The complete adsorption of the chelates took place within few seconds then, the solid was separated from the solution with the aid of a strong magnet. Cd and Pb ions were desorbed from the material with 1 mL of acid nitric 5% solution and quantified by GFAAS. All experimental and instrumental variables were optimized. The analytical performances of the optimized method were: EF (Enrichment factor): 200 with LODs (detection limit): 0.005 and 0.004 µg L-1 and LOQs (determination limit): 0.017 and 0.013 µg L-1, for Cd and Pb, respectively. The reliability of the developed procedure was tested by relative standard deviation (% RSD), which was found to be < 5%. The accuracy of the proposed method was verified using certified reference materials (SLRS-5, SPS-SW2, and BCR-723) and by determining the analyte content in spiked aqueous samples. Sea waters and tap water samples collected from Málaga (Spain) were also analysed. The determined values were in good agreement with the certified values and the recoveries for the spiked samples were around 100% in all cases.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

    Magnetic dispersive solid phase microextraction coupled with on-line chemical vapor generation method to extraction/preconcentration of mercury from environmental samples and determination by graphite furnace atomic absorption spectrometry.

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    Mercury (Hg) is classified as priority hazardous substances. Concentrations found in the aquatic environment are at trace levels as result of natural processes, such as erosion and volcanism, and anthropogenic discharges related mainly to industrial and mining activities. Mercury is one of the most potent neurotoxins known, showing a high number of adverse health effects in animals and humans. For this reason, a simple and rapid method for the determination and preconcentration of mercury in environmental waters is proposed. This work is based on magnetic dispersive solid phase microextraction (MDSPME) coupled with on-line chemical vapour generation (CVG). Graphite furnace atomic absorption spectrometry (GFAAS) was employed for the quantification of Hg. In the preconcentration step, a shell structured Fe3O4@graphene oxide was suspended in the ionic liquid carrier (1-n-butyl-3-metilimidazolium tetrafluoroborate [BMIM][BF4]), obtaining a stable colloidal suspension called ferrofluid. This sorbent possesses as large contact surface area and a high density of polar groups on its surface. The nanoparticles, when finely dispersed in the sample solution, result in almost complete extraction of Hg within a few seconds. All experimental and instrumental variables were optimized and the method was adequately validated by the analysis of certified reference materials of environmental waters. Acknowledgements The authors would like to thank Plan Propio “Proyecto Puente” de la Universidad de Málaga for financial support of this work.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

    Solid sampling determination of ZnO nanoparticles in eyeshadows by graphite furnace atomic absorption spectrometry

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    The application of nanoparticles (NPs) in science and technology is a fast growing field. Therefore, reliable and straightforward analytical methods are required for their fast determination in different types of samples. In this work, a method that enables the determination of the average size of ZnO NPs, besides their concentration, discriminating them from ionic zinc, has been optimized. The method is based on solid sampling high-resolution continuum source electrothermal atomic absorption spectrometry (SS-HR-CS-GFAAS), and has been applied to determination and characterization of ZnO NPs in cosmetic samples. Recently, graphite furnace atomic absorption spectrometry has been introduced as a new tool to determine the size of nanoparticles by evaluation of the following parameters: atomization delay (tad) and atomization rate (kat). In this work both parameters (besides peak area) have been obtained from absorbance signals for a line of Zn with low sensitivity. Two multiple response surface designs have been used in order to optimize the adequate furnace program to achieve our aims. All the optimization experiments were performed using baby´s skin irritation protective cream. The optimized furnace program is shown in Table 1. Table 1. Optimized furnace program The size calibrations were performed against solid (powered) ZnO standards, from 50-nm to 500-nm sized nanoparticles. The correlation coefficients (R value) of the linear calibration were not worse than 0.9982. The optimized method was tested in other types of cosmetic samples such as eyeshadow samples with good results. The determination of the MNPs’ size was validated by transmission electron microscopy (TEM) and the Zn concentration in the solid samples was validated by atomic fluorescence spectroscopy (AFS). Acknowledgements (optional) [Garamond font, 10 points] The authors would like to thank Plan propio “Proyecto Puente” de la Universidad de Málaga for financial support of this work.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

    Rapid magnetic microextraction to preconcentrate and determinate cadmium from environmental samples

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    A novel and greener ultrasonically assisted/modified cloud point extraction procedure for the preconcentration and extraction of trace cadmium from environmental samples was developed. The sorbent material was fabricated by scattering of magnetic iron nanoparticles (MNPs) over graphene oxide (GO) to obtain magnetic graphene oxide (MGO). The material was suspended in the ionic liquid 1-n-butyl-3-metilimidazolium tetrafluoroborate [BMIM][BF4]. The obtained stable colloidal suspension is named ferrofluid. GO presents excellent adsorbent properties for organic species due to the presence of the electronic π system. For this reason, the organic ligand [1,5-bis-(2-dipyridyl) methylene] thiocarbonohydrazide (DPTH) was used in order to form an organic complex of Cd. Once the DPTH ligand has been added to sample, the ferrofluid was injected and finely dispersed in the sample solution in order to extract the formed chelate as shown in Fig. 1. The complete adsorption of the quelate took place within few seconds, after that the solid was separated from the solution with the aid of a strong magnet. Cadmium ions were desorbed from the material with 1 mL of 5% acid nitric solution and quantified by electrothermal atomic absorption spectrometry (ETAAS). The main parameters affecting the extraction and the furnace program were optimized using one-at-time method. The analytical performance under optimum conditions are the following: LOD: 0.005 µg/L, LOQ: 0.017 µg/L. Linear calibration: 0-0.25 µg/L and EF: 200. The reliability of the developed procedure was tested by relative standard deviation (% RSD), which was found to be < 5% (1.3%). The performance of the proposed procedure was checked by applying to certified reference material and spiking standard in real samplesUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    A Configurable Event-Driven Convolutional Node with Rate Saturation Mechanism for Modular ConvNet Systems Implementation

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    Convolutional Neural Networks (ConvNets) are a particular type of neural network often used for many applications like image recognition, video analysis or natural language processing. They are inspired by the human brain, following a specific organization of the connectivity pattern between layers of neurons known as receptive field. These networks have been traditionally implemented in software, but they are becoming more computationally expensive as they scale up, having limitations for real-time processing of high-speed stimuli. On the other hand, hardware implementations show difficulties to be used for different applications, due to their reduced flexibility. In this paper, we propose a fully configurable event-driven convolutional node with rate saturation mechanism that can be used to implement arbitrary ConvNets on FPGAs. This node includes a convolutional processing unit and a routing element which allows to build large 2D arrays where any multilayer structure can be implemented. The rate saturation mechanism emulates the refractory behavior in biological neurons, guaranteeing a minimum separation in time between consecutive events. A 4-layer ConvNet with 22 convolutional nodes trained for poker card symbol recognition has been implemented in a Spartan6 FPGA. This network has been tested with a stimulus where 40 poker cards were observed by a Dynamic Vision Sensor (DVS) in 1 s time. Different slow-down factors were applied to characterize the behavior of the system for high speed processing. For slow stimulus play-back, a 96% recognition rate is obtained with a power consumption of 0.85mW. At maximum play-back speed, a traffic control mechanism downsamples the input stimulus, obtaining a recognition rate above 63% when less than 20% of the input events are processed, demonstrating the robustness of the networkEuropean Union 644096, 687299Gobierno de España TEC2016-77785- P, TEC2015-63884-C2-1-PJunta de Andalucía TIC-6091, TICP120

    Satellite potentials for hypergeometric Natanzon potentials

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    As a result of the so(2,1) of the hypergeometric Natanzon potential a set of potentials related to the given one is determined. The set arises as a result of the action of the so(2,1) generators.Comment: 9 page

    Semiautomatic method for the ultra-trace arsenic speciation in environmental waters via magnetic solid phase extraction prior to HPLC-ICP-MS determination

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    SHOTGUN PRESENTATIONA new magnetic functionalized material based on graphene oxide magnetic nanoparticles (MGO) was designed and characterized in order to develop a magnetic solid phase extraction method (MSPE) to enrich both inorganic and organic arsenic species in environmental waters. A FIA system is used to preconcentrate the arsenic species simultaneously, while the ultra-trace separation and determination of arsenobetaine (AsBet), cacodylate, As(III) and As(V) species have been achieved by high performance liquid chromatography coupled to inductively coupled plasma mass spectrometry (HPLC-ICP-MS) technique. The sample is introduced in the FIA system where the MSPE takes place, and 1 ml of eluent is collected in a chromatographic vial. After preconcentration, the vial is introduced in the autosampler of HPLC-ICP-MS. Therefore, preconcentration and separation/determination processes are automatic and conducted separately (Figure 1). The strategy of this work was focused on the compatibility between the MSPE eluent and the mobile phase of HPLC column system, resulting in an efficient and reliable semiautomatic preconcentration and detection of inorganic and organic arsenic speciation. To the best of our knowledge, this is the first method combining an online MSPE and HPLC-MS, and one of the first using a magnetic nanomaterial based on MGO for online MSPE. Under the optimized conditions, the preconcentration factors obtained for AsBet, cacodilate, As(III) and As(V) with 12 mL sample solution were 4, 12, 6 and 19, respectively. The LODs for the arsenic species were AsBet 7 ng L -1, cacodylate 0.4 ng L-1, As(III) 1.0 ng L-1 and As(V) 0.2 ng L-1 and RSDs < 5%. The developed method was validated by analyzing tap water, well water and seawater samples, and Certified Reference Materials; fortified lake water TMDA 64.3 and seawater Cass-6 NRC, promising for routine monitoring of arsenic species in environmental waterUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech Fondos FEDER y Junta de Andalucía Proyecto UMA18-FEDERJA-060 Plan Propio, Proyecto Puente, Universidad de Málag
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