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Autorizo (autorizamos) a la Biblioteca de la Institución para que incluya una copia, indexe y divulgue en el Repositorio Institucional, la obra mencionada con el fin de facilitar los procesos de visibilidad e impacto de la misma, conforme a los derechos patrimoniales que me(nos) corresponde(n) y que incluyen: la reproducción, comunicación pública, distribución al público, transformación, de conformidad con la normatividad vigente sobre derechos de autor y derechos conexos referidos en art. 2, 12, 30 (modificado por el art 5 de la ley 1520/2012), y 72 de la ley 23 de de 1982, Ley 44 de 1993, art. 4 y 11 Decisión Andina 351 de 1993 art. 11, Decreto 460 de 1995, Circular No 06/2002 de la Dirección Nacional de Derechos de autor, art. 15 Ley 1520 de 2012, la Ley 1915 de 2018 y demás normas sobre la materia. Al respecto como Autor(es) manifestamos conocer que: - La autorización es de carácter no exclusiva y limitada, esto implica que la licencia tiene una vigencia, que no es perpetua y que el autor puede publicar o difundir su obra en cualquier otro medio, así como llevar a cabo cualquier tipo de acción sobre el documento. - La autorización tendrá una vigencia de cinco años a partir del momento de la inclusión de la obra en el repositorio, prorrogable indefinidamente por el tiempo de duración de los derechos patrimoniales del autor y podrá darse por terminada una vez el autor lo manifieste por escrito a la institución, con la salvedad de que la obra es difundida globalmente y cosechada por diferentes buscadores y/o repositorios en Internet lo que no garantiza que la obra pueda ser retirada de manera inmediata de otros sistemas de información en los que se haya indexado, diferentes al repositorio institucional de la Institución, de manera que el autor(res) tendrán que solicitar la retirada de su obra directamente a otros sistemas de información distintos al de la Institución si desea que su obra sea retirada de inmediato. - La autorización de publicación comprende el formato original de la obra y todos los demás que se requiera para su publicación en el repositorio. Igualmente, la autorización permite a la institución el cambio de soporte de la obra con fines de preservación (impreso, electrónico, digital, Internet, intranet, o cualquier otro formato conocido o por conocer). - La autorización es gratuita y se renuncia a recibir cualquier remuneración por los usos de la obra, de acuerdo con la licencia establecida en esta autorización. - Al firmar esta autorización, se manifiesta que la obra es original y no existe en ella ninguna violación a los derechos de autor de terceros. En caso de que el trabajo haya sido financiado por terceros el o los autores asumen la responsabilidad del cumplimiento de los acuerdos establecidos sobre los derechos patrimoniales de la obra con dicho tercero. - Frente a cualquier reclamación por terceros, el o los autores serán responsables, en ningún caso la responsabilidad será asumida por la institución. - Con la autorización, la institución puede difundir la obra en índices, buscadores y otros sistemas de información que favorezcan su visibilidad

Recent Submissions

Twitter data mining for the diagnosis of leaks in drinking water distribution networks

Jiménez-Cabas, Javier; Torres, Lizeth; Lozoya-Santos, Jorge de Jesús (MDPI AGSwitzerland, 2023-03-14)

This article presents a methodology for using data from social networks, specifically from Twitter, to diagnose leaks in drinking water distribution networks. The methodology involves the collection of tweets from citizens ...
Privacy preserving blockchain with energy aware clustering scheme for iot healthcare systems

Escorcia-Gutierrez, José; Mansour, Romany F.; Leal, Esmeide; Villanueva, Jair; Jiménez-Cabas, Javier; Soto, Carlos; Soto-Diaz, Roosvel (Springer NetherlandsNetherlands, 2023)

Due to advancements in information technology, the healthcare sector becomes beneficial and provides distinct methods of managing medical data and enhancing the quality of medical services. The advanced e-healthcare ...
Technologies for the preservation of cultural heritage—a systematic review of the literature

Diaz Mendoza, Maria Antonia; De-La-Hoz-Franco, Emiro; Gomez, Jorge (MDPI AGSwitzerland, 2023)

first_pagesettingsOrder Article Reprints Open AccessReview Technologies for the Preservation of Cultural Heritage—A Systematic Review of the Literature by María Antonia Diaz Mendoza 1,*ORCID,Emiro De La Hoz Franco 1ORCID ...
On the relation between monocultures and ecosystem services in the Global South: a review

Suarez, Andrés; Gwozdz, Wencke (Elsevier BVNetherlands, 2023)

The countries of the global south are characterized by high levels of biodiversity. In addition, these countries have suffered -and will suffer- even more ecological pressures due to agricultural production, mainly ...
On the influence of drained cyclic preloadings on the cyclic behaviour of Zbraslav sand

Duque, J.; Roháč, J.; Mašín, D. (Elsevier BVUnited Kingdom, 2023)

This article experimentally evaluates the influence of directional drained cyclic preloadings on the subsequent undrained monotonic and cyclic response of Zbraslav sand. The cyclic tests were performed on dense samples and ...
Influence of ambient temperature in the city of Portoviejo, Ecuador on the energy performance of photovoltaic modules

EPENI-TOMBO, GENIAL BELVINEL; Rodríguez Gámez, María; Loor Castillo, Guillermo Antonio; Vázquez Pérez, Antonio; Núñez Alvarez, José Ricardo (Institute of Advanced Engineering and Science (IAES)Indonesia, 2023)

The research analyzes the influence of the average temperature on the performance of specific photovoltaic solar modules under the environmental conditions of the city of Portoviejo, province of Manabí, Ecuador. The research ...
Green building's heat loss reduction analysis through two novel hybrid approaches

Moayedi, Hossein; YILDIZHAN, Hasan; Aungkulanon, Pasura; Cardenas Escorcia, Yulineth; Al-Bahrani, Mohammed; Binh, Le Nguyen (Elsevier Ltd.United Kingdom, 2023)

One of the key reasons for the performance discrepancy between a building's intended usage and the actual operation is Heat Loss, which describes a building's envelope efficiency during in-use circumstances. In this setting, ...
Exploitation of Bauhinia forficata residual fruit powder for the adsorption of cationic dyes

lotfi, sellaoui; Bouzidib, Mohamed; Franco, Dison S.P.; Alshammari, Abdullah S.; Gandouzi, Mohamed; georgin, jordana; Haj Mohamed, Naim Bel; Erto, Alessandro; Badawi, Michael (ElsevierNetherlands, 2023)

This paper analyzes the adsorption of two potential toxic dyes, i.e. methylene blue (MB) and crystal violet (CV) onto Bauhinia forficata residual fruit powder (BFRFP) as a new promising adsorbent. The experiments aimed at ...
El patrimonio cultural inmueble como derecho colectivo. Consideraciones sobre su protección y conservación en Colombia.

Larios Giraldo, Paola Milena; CABRERA, IRINA (Chile, 2021-06-30)

El presente documento analiza el proceso de elaboración y aplicación de los Planes especiales de manejo y Protección en Colombia y las implicaciones de su aplicación en la preservación de inmuebles del sector patrimonial ...
Development and validation of a prototype for the on-line simultaneous analysis of quality caprolactam synthesized on an industrial scale

Hernández Fernández, Joaquín; Rincón, David; López-Martínez, Juan (Elsevier BVNetherlands, 2023)

Caprolactam is a highly useful monomer obtained through the Beckmann arrangement, which generates large profits worldwide and is widely used in different industries. During the synthesis process, various components can be ...
Designing multifunctional biocatalytic cascade system by multi-enzyme co-immobilization on biopolymers and nanostructured materials

Tan, Zhongbiao; Cheng, Hairong; Chen, Gang; Ju, Fang; Fernández-Lucas, Jesús; Zdarta, Jakub; JESIONOWSKI, TEOFIL; Bilal, Muhammad (ElsevierNetherlands, 2023)

In recent decades, enzyme-based biocatalytic systems have garnered increasing interest in industrial and applied research for catalysis and organic chemistry. Many enzymatic reactions have been applied to sustainable and ...
Critical rare earth metal adsorption onto expanded vermiculite: accurate modeling through response surface methodology and machine learning techniques

de Vargas Brião, Giani; Pfingsten Franco, Dison Stracke; Vasconcelos da Silva, Flávio; Carlos da Silva, Meuris Gurgel; Gurgel Adeodato Vieira, Melissa (Elsevier BVNetherlands, 2023)

The circular economy of rare earth metals (REM), such as dysprosium, is essential for a sustainable future in clean energy and high-tech fields. Adsorption has gained attention to recover and reintegrate REM into the ...
Air pollution in central European capital (Budapest) via self-made passive samplers and Sentinel-3B SYN satellite images

Neckel, Alcindo; Silva Oliveira, Marcos Leandro; Stolfo Maculan, Laércio; Bodah, Brian William; Gonçalves Jr., Affonso Celso; Silva Oliveira, Luis Felipe (Elsevier BVNetherlands, 2023)

This study is to identify the types of ultra-fine air pollutants present in the local atmosphere. The authors utilize Sentinel-3B SYN satellite images to identify the presence of Aerosol Optical Thickness (T550), and later ...
A universal model of three-phase asynchronous motors for electrical power system analysis

Collazo Solar, Laura; Costa Montiel, Ángel A.; Vilaragut Llanes, Miriam; Sousa Santos, Vladimir; de la Incera Núñez, Carlos (Institute of Advanced Engineering and Science (IAES)Indonesia, 2023)

The high incidence of three-phase asynchronous motors (TAM) in global energy consumption and its influence on the operation of electrical systems makes it necessary to develop models that allow their analysis effectively. ...
Treatment of residual lubricating oil using rice husk-based material as ecological adsorbent

Farias, R. B. H. B.; Pinto, D.; Goulart, M. L.; Igansi, A. V.; Loebens, L.; Yılmaz, M.; Silva Oliveira, Luis Felipe; Andreazza, R.; Cadaval Jr, T. R. S.; Quadro, M. S. (Springer JapanJapan, 2023)

One of the most significant environmental problems the world population faces is the inadequate disposal of petroleum derivatives. Lubricant oil is a hazardous waste due to its properties and characteristics. This study ...
Neuropsychological effects and cognitive deficits associated with exposure to mercury and arsenic in children and adolescents of the Mojana region, Colombia

Argumedos De la Ossa, César; Ramírez-Giraldo, Andrés Fernando; Arroyo Alvis, Katy Estela; Marrugo-Negrete, José; Díez, Sergi (Academic Press Inc.United States, 2023)

The present study aims to explore the neuropsychological performance and exposure to mercury (Hg) and arsenic (As) in Colombian children and adolescents considering biomarkers in hair and blood. The total sample consisted ...
Conversion of foliar residues of Sansevieria trifasciata into adsorbents: dye adsorption in continuous and discontinuous systems

Grassi, Patrícia; Schadeck Netto, Matias; Jahn, Sérgio Luiz; georgin, jordana; Franco, Dison S. P.; Sillanpää, Mika; Meili, Lucas; Silva Oliveira, Luis Felipe (Springer Science + Business MediaGermany, 2022-09-04)

The study analyzed the potential of leaf powder prepared from the residual leaves of the species Sansevieria trifasciata, as a potential adsorbent for methylene blue (MB) removal. The equilibrium was reached fast for almost ...
Sexual-specific disgust sensitivity mechanisms in homonegativity and transnegativity; the mediating role of right-wing authoritarianism (RWA)

Chamorro Coneo, Ana Maria; Navarro, Maria Camila; Quiroz Molinares, Nathalia (RoutledgeUnited Kingdom, 2023)

Disgust specific to sexual stimuli has been thought to be an adaptation that serves purposes of pathogen-avoidance, partner selection and social dominance. While the link between disgust responses and homonegative and ...
Using feed-forward perceptron Artificial Neural Network (ANN) model to determine the rolling force, power and slip of the tandem cold rolling

Xia, J.S.; Khabaz, Mohamad Khaje; Patra, Indrajit; Khalid, Imran; Núñez Álvarez, José Ricardo; Rahmanian, Alireza; Eftekhari, S. Ali; Toghraie, Davood (ISA - Instrumentation, Systems, and Automation SocietyUnited States, 2023)

In this paper, an Artificial Neural Network (ANN) is used to investigate the influence of rolling parameters such as thickness reduction, inter-strand tension, rolling speed and friction on the rolling force, rolling power, ...
Psychophysiological and psychosocial profile of patients attending drug addiction centers

Clemente-Suárez, Vicente Javier; Ruisoto, Pablo; Manuel, Isorna Folgar; Cancelo-Martínez, Jesús; Beltrán-Velasco, Ana Isabel; Tornero-Aguilera, José Francisco (Springer New YorkUnited States, 2021-12-27)

Drug treatment centres provide the highest level of rehab services for patients diagnosed with drug addictions. Most inpatient drug rehab programs focus on medical detox and mental health interventions. However, how to ...

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Artículos científicos
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Artículos de investigación publicados por miembros de la comunidad universitaria.

LEER
Twitter data mining for the diagnosis of leaks in drinking water distribution networks
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Jiménez-Cabas, Javier | 2023-03-14

This article presents a methodology for using data from social networks, specifically from Twitter, to diagnose leaks in drinking water distribution networks. The methodology involves the collection of tweets from citizens reporting leaks, the extraction of information from the tweets, and the processing of such information to run the diagnosis. To demonstrate the viability of this methodology, 358 Twitter leak reports were collected and analyzed in Mexico City from 1 May to 31 December 2022. From these reports, leak density and probability were calculated, which are metrics that can be used to develop forecasting algorithms, identify root causes, and program repairs. The calculated metrics were compared with those calculated through telephone reports provided by SACMEX, the entity that manages water in Mexico City. Results show that metrics obtained from Twitter and phone reports were highly comparable, indicating the usefulness and reliability of social media data for diagnosing leaks.

LEER
Privacy preserving blockchain with energy aware clustering scheme for iot healthcare systems
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Escorcia-Gutierrez, José | 2023

Due to advancements in information technology, the healthcare sector becomes beneficial and provides distinct methods of managing medical data and enhancing the quality of medical services. The advanced e-healthcare applications are mainly based on the Internet of Things (IoT) and cloud computing platforms. In IoT enabled healthcare sector, the IoT devices usually record the patient data and transfer it to the cloud for further processing. Energy efficiency and security are treated as critical problems in designing IoT networks in the healthcare environment. As IoT devices are limited to energy, designing an effective technique to reduce energy utilization is needed. At the same time, secure transmission of medical data also poses a major challenging design issue. This paper presents a novel artificial intelligence with a blockchain scheme for IoT healthcare systems named AIBS-IoTHS. The AIBS-IoTH model aims to achieve secure and energy-efficient data transmission in IoT networks. The IoT devices are primarily used to collect patients’ medical data. The AIBS- IoTH model involves a metaheuristic-based modified sunflower optimization-based clustering (MSFOC) technique to achieve energy efficiency. Then, the blockchain empowered secure medical data transmission process is carried out for both inter-cluster and intra-cluster communication. At last, the Classification Enhancement Generative Adversarial Networks (CEGAN) model performs the diagnostic process on the secured medical data to determine the existence of the diseases. The design of MSFOC and CEGAN techniques shows the novelty of the work. An extensive experimental analysis of the benchmark dataset pointed out the superior performance of the proposed AIBS-IoTH model over the other compared methods.

LEER
Technologies for the preservation of cultural heritage—a systematic review of the literature
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Diaz Mendoza, Maria Antonia | 2023

first_pagesettingsOrder Article Reprints Open AccessReview Technologies for the Preservation of Cultural Heritage—A Systematic Review of the Literature by María Antonia Diaz Mendoza 1,*ORCID,Emiro De La Hoz Franco 1ORCID andJorge Eliecer Gómez Gómez 2ORCID 1 Department of Computer Science and Electronics, Faculty of Engineering, Universidad de la Costa CUC, Barranquilla 080002, Colombia 2 Department of Systems Engineering and Telecommunications, Faculty of Engineering, Universidad de Córdoba, Montería 230002, Colombia * Author to whom correspondence should be addressed. Sustainability 2023, 15(2), 1059; https://doi.org/10.3390/su15021059 Received: 17 November 2022 / Revised: 28 December 2022 / Accepted: 3 January 2023 / Published: 6 January 2023 (This article belongs to the Section Tourism, Culture, and Heritage) Download Browse Figures Review Reports Versions Notes Abstract This work establishes the technological elements that have enabled the preservation, promotion, and dissemination of tangible and intangible cultural heritage in the period from 2018 to 2022. For this, a Systematic Literature Review (SLR) was conducted in the scientific databases Scopus, Science Direct, IEEE and Web of Science, which facilitated the identification of 146 articles related to the topic. A quantitative and qualitative analysis of the journals, authors and topics was carried out, detailing the important variables required to establish the sought-out elements; for this purpose, the following were quantified in the papers: type, topic, categorization, country, and language; in the publications, the type of heritage chosen, the place of the heritage and the type of intervention were investigated. The number of publications reporting the use of some type of technology was also identified, finding that 70% of them show a technological approach to preserve cultural heritage, while 30% refer to other types of interventions. The technologies reported to be used the most are 3D digital technologies (44% of those showing technological applications), augmented reality or virtual reality, henceforth AR/VR (15%).

LEER
On the relation between monocultures and ecosystem services in the Global South: a review
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Suarez, Andrés | 2023

The countries of the global south are characterized by high levels of biodiversity. In addition, these countries have suffered -and will suffer- even more ecological pressures due to agricultural production, mainly monocultures. When considering areas of high biodiversity with highly intensive agricultural systems, the scientific literature highlights the role provided by Ecosystem Services (ES) both to monocultures and from monocultures to their contexts. In this sense, the objective of this paper is to provide a Systematic Literature Review (SLR) to understand the relationship between monocultures and ES in the global south. Furthermore, in this research we provide a context analysis to broaden the understanding of the implications of monocultures in this region. We provide correlations between trends in monocultures harvested areas and forest cover in the countries identified through the SLR. Our SLR identified information from 15 countries and 11 monocultures. We found several negative correlations between harvested area and forest cover, mainly in megadiverse countries. In addition, we depicted trade-offs and synergies related to monocultures. We conclude that more research is needed in this regard, especially since there is great interest in monocultures for economic development in the global south, and this area will support world food production in the future.

LEER
On the influence of drained cyclic preloadings on the cyclic behaviour of Zbraslav sand
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Duque, J. | 2023

This article experimentally evaluates the influence of directional drained cyclic preloadings on the subsequent undrained monotonic and cyclic response of Zbraslav sand. The cyclic tests were performed on dense samples and under triaxial conditions. The experiments considered several different preloading directions, magnitude of the maximum deviatoric stress reached during the drained preloading stage and deviatoric stress amplitudes during the undrained shearing stage. The experimental results suggested that the rate of strains and pore water pressure accumulation, and therefore, the number of cycles to reach initial liquefaction or failure conditions are remarkably affected by the direction of the drained preloading history. In addition, the preloading direction plays a major role on the contractive/dilative response during the subsequent undrained monotonic loading. In particular, directional drained cyclic preloadings toward positive deviatoric stresses at constant mean effective stress and isotropic compression led to more dilative responses. Contrary, preloadings toward negative deviatoric stresses at constant mean effective stress led to more contractive responses. The results suggest that these major variations cannot be associated to the rather small changes in the relative density of the samples but likely due to fabric changes and induced anisotropy caused by the drained preloading history.

LEER
Influence of ambient temperature in the city of Portoviejo, Ecuador on the energy performance of photovoltaic modules
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EPENI-TOMBO, GENIAL BELVINEL | 2023

The research analyzes the influence of the average temperature on the performance of specific photovoltaic solar modules under the environmental conditions of the city of Portoviejo, province of Manabí, Ecuador. The research is carried out using the qualitative methodology. Its main objective is to determine the influence of temperature on the energy performance of photovoltaic modules under the region's environmental conditions. Two electrical diagrams with different configurations were designed, which were analyzed and simulated using the MATLAB Simulink software. The results obtained show the direct relationship between the electrical parameters of voltage, current intensity, and power with the temperature value on the surface of the modules. It is concluded that the modules generate a higher value of voltage, electric current intensity, and electric power at a lower temperature, regardless of the level of solar irradiation they receive.

LEER
Green building's heat loss reduction analysis through two novel hybrid approaches
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Moayedi, Hossein | 2023

One of the key reasons for the performance discrepancy between a building's intended usage and the actual operation is Heat Loss, which describes a building's envelope efficiency during in-use circumstances. In this setting, the ANN models’ use for energy analysis of green buildings has become more established. This research aims to anticipate the heat loss of green buildings utilizing two artificial neural network-based methodologies (ANN). In particular, TLBO and BBO are used and contrasted. Additionally, RMSE, MAE, and R2 are used to calculate an absolute error for predicting heat loss to gauge the accuracy of the findings. The suggested TLBO-MLP standard is a reliable method with a positive outcome (RMSE = 0.01012 and 0.05216, and R2 = 0.99536 and 0.9651). Also, according to the training error ranges of [−0.0006078, 0.01133] and [−0.00040708, 0.010181] and testing error ranges of [0.0004724, 0.068666] and [0.0021984, 0.057688] for BBO-MLP and TLBO-MLP, respectively, shows that the TLBO-MLP reaches the lower range of error and can predict the heat loss with higher accuracy and it could properly forecast the heat loss of building technologies. Even so, the BBO-MLP standard provides this research with satisfactory performance (R2 = 0.9943 and 0.95175, and RMSE = 0.01122 and 0.06112). To increase the precision of calculating the heat loss of buildings, specifically integrating them with optimization algorithms, further study is required.

LEER
Exploitation of Bauhinia forficata residual fruit powder for the adsorption of cationic dyes
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lotfi, sellaoui | 2023

This paper analyzes the adsorption of two potential toxic dyes, i.e. methylene blue (MB) and crystal violet (CV) onto Bauhinia forficata residual fruit powder (BFRFP) as a new promising adsorbent. The experiments aimed at retrievement of adsorption data are carried out at T = 298–328 K and are coupled with an adsorbent characterization to better highlight the MB and CV dyes adsorption mechanism. MB adsorption capacity at saturation (ACS) varies from 181.48 to 201 mg.g−1, while for CV dye, it ranges from 263.06 to 282.61 mg.g−1. This difference is not very significant but reflects that the BFRFP has a higher affinity to remove CV dye. Comparing with some alternative adsorbents, the BFRFP adsorbent shows to be a competitive material for the removal of MB and CV dyes from polluted water. A model assuming that MB and CV dyes are removed via a formation of two layers on BFRFP is chosen as the one that, from a physical point of view, better interpret their adsorption mechanisms. The prediction of the number of dyes adsorbed on BFRFP is approximately equal to 1 for both the dyes, testifying that they are removed without an aggregation process and with slanted position. The physical model generates two energies to describe the interactive effects between both dyes and BFRFP adsorbent (dye- BFRFP) and between dyes (dye-dye). Results show that physical interactions occur during the adsorption process.

LEER
El patrimonio cultural inmueble como derecho colectivo. Consideraciones sobre su protección y conservación en Colombia.
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Larios Giraldo, Paola Milena | 2021-06-30

El presente documento analiza el proceso de elaboración y aplicación de los Planes especiales de manejo y Protección en Colombia y las implicaciones de su aplicación en la preservación de inmuebles del sector patrimonial Barrio Prado, Alto Prado y Bella Vista, en la ciudad de Barranquilla. El estudio pone de manifiesto la disyuntiva entre los planteamientos de la teoría y las implicaciones prácticas reales en el proceso de patrimonialización. La discusión se abordó desde una perspectiva descriptiva y crítica, con una visión desde las disciplinas de la arquitectura y el derecho urbano; con datos recogidos a partir de la consulta y análisis de fuentes secundarias y entrevistas semiestructuradas con propietarios de inmuebles en el sector. El documento cierra con una reflexión e invitación a concebir el patrimonio como derecho de todos y como punto de partida para procesos que, a largo plazo, redunden en la consolidación de identidad local, así como en la gestión de un desarrollo sustentable.

LEER
Development and validation of a prototype for the on-line simultaneous analysis of quality caprolactam synthesized on an industrial scale
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Hernández Fernández, Joaquín | 2023

Caprolactam is a highly useful monomer obtained through the Beckmann arrangement, which generates large profits worldwide and is widely used in different industries. During the synthesis process, various components can be generated that weaken the quality of the final product, to have control of the monomer, monitoring is carried out during the synthesis and characterization of the final product. These characterizations generally take time due to the different techniques that must be performed to obtain the data. In this work, a method is designed that associates different techniques to reduce the number of steps carried out in the tests to determine the quality of the material, optimize the times and generate a quality and efficient process in a shorter time, in addition, it is due to a semi-automated system for the simultaneous characterization of caprolactam, which, according to the statistical data obtained for sodium, iron, volatile bases, and moisture analysis were reproducible. The developed prototype had 21 on-line valves that allowed taking the representative volumes of samples and reagents necessary for each measurement. There is excellent linearity where the correlation coefficient has values between 0,9992 and 1. The values obtained for the relative error are between 0.18 and 2.24% for laboratory tests using the traditional method and between 0.21 and 3.83% for tests carried out using the prototype. The P value of the evaluation of the means was 0.997, indicating that the means are not statistically different.

LEER
Designing multifunctional biocatalytic cascade system by multi-enzyme co-immobilization on biopolymers and nanostructured materials
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Tan, Zhongbiao | 2023

In recent decades, enzyme-based biocatalytic systems have garnered increasing interest in industrial and applied research for catalysis and organic chemistry. Many enzymatic reactions have been applied to sustainable and environmentally friendly production processes, particularly in the pharmaceutical, fine chemicals, and flavor/fragrance industries. However, only a fraction of the enzymes available has been stepped up towards industrial-scale manufacturing due to low enzyme stability and challenging separation, recovery, and reusability. In this context, immobilization and co-immobilization in robust support materials have emerged as valuable strategies to overcome these inadequacies by facilitating repeated or continuous batch operations and downstream processes. To further reduce separations, it can be advantageous to use multiple enzymes at once in one pot. Enzyme co-immobilization enables biocatalytic synergism and reusability, boosting process efficiency and cost-effectiveness. Several studies on multi-enzyme immobilization and co-localization propose kinetic advantages of the enhanced turnover number for multiple enzymes. This review spotlights recent progress in developing versatile biocatalytic cascade systems by multi-enzyme co-immobilization on environmentally friendly biopolymers and nanostructured materials and their application scope in the chemical and biotechnological industries. After a succinct overview of carrier-based and carrier-free immobilization/co-immobilizations, co-immobilization of enzymes on a range of biopolymer and nanomaterials-based supports is thoroughly compiled with contemporary and state-of-the-art examples. This study provides a new horizon in developing effective and innovative multi-enzymatic systems with new possibilities to fully harness the adventure of biocatalytic systems.

LEER
Critical rare earth metal adsorption onto expanded vermiculite: accurate modeling through response surface methodology and machine learning techniques
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de Vargas Brião, Giani | 2023

The circular economy of rare earth metals (REM), such as dysprosium, is essential for a sustainable future in clean energy and high-tech fields. Adsorption has gained attention to recover and reintegrate REM into the productive chain; however, accurate modeling of adsorptive processes still needs to be addressed, which delays further scale-up studies. Thus, this paper studied the adsorption of Dy on expanded vermiculite and applied novel empirical methods, such as artificial neural networks (ANN) and adaptive neuro-fuzzy inference system (ANFIS), and the classical response surface methodology (RSM) for modeling of dysprosium recovery as a function of adsorbent size, mass, and pH of the solution, variables often ignored in the mathematical modeling of adsorption. In our work, the effect of each operational parameter on Dy removal efficiency was examined by the RSM approach, in which only the adsorbent dosage and pH were the significant factors. So, ANFIS with two input membership functions (Gaussian type) was the most accurate procedure to predict and model the dysprosium removal efficiency (R2 = 0.99681). Also, vermiculite removed dysprosium with high efficiency (99.2%) under the best experimental conditions, at pH around 3.5 and adsorbent mass of 0.64 g, indicating an effective process optimization. The loaded vermiculite, after the adsorption, was characterized by textural and thermal properties that confirmed the stability of the material. Thus, according to basic operational parameters, accurate modeling of the Dy adsorption on expanded vermiculite (a low-cost, available, and non-toxic material) can improve adsorption technology's maturity to reconcentrate and recover rare earth metals.

LEER
Air pollution in central European capital (Budapest) via self-made passive samplers and Sentinel-3B SYN satellite images
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Neckel, Alcindo | 2023

This study is to identify the types of ultra-fine air pollutants present in the local atmosphere. The authors utilize Sentinel-3B SYN satellite images to identify the presence of Aerosol Optical Thickness (T550), and later verify this presence through physical sample collection using self-made passive samplers (SMPSs) at various locations in Budapest ((A) Passenger Cruise Port, (B) Kunsthalle, (C) Szechenyi Lanchid, and (D) Liberty Bridge). The samples obtained from the SMPSs were analyzed by X-ray Diffraction (XRD) to identify the minerals present in ultra-fine phases (e.g. minerals and ultra-fine amorphous). The images from the Sentinel-3B SYN satellite, taken between 2018, 2019 and 2021 allowed us to identify the Aerosol Optical Thickness (T550) at these same locations in Budapest. The SMPS samples revealed the presence of ultra-fine particles containing elements dangerous to human health, such as: As, Cd, Cr, Hg, Pb, Ti, V and Ni. The points analyzed in the Sentinel-3B SYN satellite images showed a 50.89% reduction in T550 levels in the city of Budapest, attributed to the COVID-19 epidemic, which clearly demonstrates the need to reduce pollutants for a better quality of life in this central capital of Europe.

LEER
A universal model of three-phase asynchronous motors for electrical power system analysis
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Collazo Solar, Laura | 2023

The high incidence of three-phase asynchronous motors (TAM) in global energy consumption and its influence on the operation of electrical systems makes it necessary to develop models that allow their analysis effectively. Based on this, this paper presents a universal model of TAM based on the relationship between the active and reactive power of the TAM and the deviation of voltage and frequency. It can be applied to any general-purpose TAM and is very useful when representing these motors in electrical power system studies. The model parameters were obtained from a statistical analysis performed on 70 TAM of different classifications. The results are validated by comparing them with those obtained from the solution of the equivalent circuit, demonstrating its validity by less than 6% errors.

LEER
Treatment of residual lubricating oil using rice husk-based material as ecological adsorbent
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Farias, R. B. H. B. | 2023

One of the most significant environmental problems the world population faces is the inadequate disposal of petroleum derivatives. Lubricant oil is a hazardous waste due to its properties and characteristics. This study is a new proposal for using rice waste as an adsorbent to remove lubricating oils from a water medium. Rice husk from local industries was prepared using four different techniques: thermal treatment, alkaline treatment, acid treated and without treatment. The experiment used a mineral-based lubricating oil for gasoline and ethanol engines as adsorbate. Absorbents were characterized using thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), morphological structure (SEM), energy-dispersive spectroscopy (EDS), Fourier transform infrared (FTIR) spectroscopy, and X-ray diffraction (XRD) analysis. Specific surface area and pore size distribution (BET/BJH). The adsorbent without treatment showed the smallest surface area (0.79 m2 g−1), while the adsorbent produced using acid treatment showed the largest (3.71 m2 g−1). The adsorption kinetic behavior was obtained by adjusting the pseudo-first-order, pseudo-second-order, and Elovich models. Elovich models showed more adequate results to represent the kinetic profile. The adsorbents showed high adsorption capacities, ranging from 1650 to 2000 mg g−1. The adsorbent produced using heat treatment (RH-H) was the most efficient for removing lubricating oil.

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Neuropsychological effects and cognitive deficits associated with exposure to mercury and arsenic in children and adolescents of the Mojana region, Colombia
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Argumedos De la Ossa, César | 2023

The present study aims to explore the neuropsychological performance and exposure to mercury (Hg) and arsenic (As) in Colombian children and adolescents considering biomarkers in hair and blood. The total sample consisted of 70 participants from the Mojana region, Colombia. A neuropsychological evaluation protocol was used, consisting of 11 internationally recognized tests, with evidence of national validation and use for measurement in neurotoxicology contexts. A 57.1% of the sample presented levels above the reference value according to the USEPA, the WHO, and the ATSDR for total mercury in hair (HgH), blood mercury (HgB), and/or blood arsenic (AsB). The mean values reported for HgH were 1.76 ± 3.1 μg/g (95% CI 1.02–2.50) with ranges between 0.23 and 17.20; for HgB: 4.11 ± 5.93 μg/l (CI 2.69–5.52), ranging between 0.25 and 25.80, and for AsB: 1.96 ± 2.73 (CI 1.31–2.61) ranging between 0.50 and 15.50. In the comparison of groups in relation to the level of exposure, a significant difference was found (p < 0.05) for the subtest The Boston Naming Test (BNT). Correlation analyses found, on the one hand, significant negative relationships in tests integrated within the verbal (CVB) and executive function (EF) components as well as evidence of positive relationships in the manifestation of errors in their performance with the levels of Hg and/or As transformed by biomarker (Log10). In the linear regression analyses it was found that for each increase in the concentration of HgH, HgB, and AsB it is estimated that, both for the models with and without data adjustment, there is a loss of scores in integrated measures within the CVB and EF for the transformed levels of HgH, HgB, and AsB; and an increase in the reported errors in their processing within these functions. According to these results, exposure to mercury and/or arsenic is related with performance in verbal neuropsychological skills and executive functioning.

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Conversion of foliar residues of Sansevieria trifasciata into adsorbents: dye adsorption in continuous and discontinuous systems
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Grassi, Patrícia | 2022-09-04

The study analyzed the potential of leaf powder prepared from the residual leaves of the species Sansevieria trifasciata, as a potential adsorbent for methylene blue (MB) removal. The equilibrium was reached fast for almost all concentrations after 60 min, obtaining the maximum capacity of 139.98 mg g−1 for 200 mg L−1. The increase in temperature disfavored the dye adsorption, with the maximum adsorption capacity of 225.8 mg g−1, observed for 298 K. The thermodynamic parameters confirmed that the adsorption process is spontaneous and exothermic. A direct sloping curve was established for the fixed bed, with breakthrough time (tb), column stoichiometric capacities (qeq), and the mass transfer zone lengths (Zm) were 1430, 1130, and 525 min; 60.48, 187.01, and 322.65 mg g−1; and 8.81, 11.28, and 10.71 cm, for 100, 200, and 500 mg L−1, respectively. Furthermore, in a mixture of several dyes, the adsorbent obtained the removal of 51% of the color.

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Sexual-specific disgust sensitivity mechanisms in homonegativity and transnegativity; the mediating role of right-wing authoritarianism (RWA)
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Chamorro Coneo, Ana Maria | 2023

Disgust specific to sexual stimuli has been thought to be an adaptation that serves purposes of pathogen-avoidance, partner selection and social dominance. While the link between disgust responses and homonegative and transnegative attitudes has been relatively established, it is not yet clear why. Literature using evolutionary psychology perspectives of these phenomena is scarce in areas with substantial LGBT-related violence like Colombia. This research aimed to study the interplay of predispositional (e.g. sociodemographic, reported contact), affective (e.g. disgust sensitivity) and cognitive (e.g. Right-Wing Authoritarian) variables in homonegative and transnegative attitudes of Colombian adults. Participants (N = 272) had a mean age of 26.38 (SD = 9.47), women comprised 72% of the sample and men 28%. Hierarchical regression analyses showed that increased sexual specific disgust sensitivity and greater RWA predicted stronger homonegativity and transnegativity. The relationship between sexual disgust and prejudice was partially mediated by RWA. Findings suggest that sexual disgust sensitivity adaptations in homonegativity and transnegativity may respond to selection pressures that differ from pathogen-avoidance perspectives, and that are associated with maintaining social hierarchy and social dominance. Anti-prejudice initiatives would benefit from targeting emotional responses of sexual disgust, especially within communities and institutions that have historically endorsed conservative and traditional values.

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Using feed-forward perceptron Artificial Neural Network (ANN) model to determine the rolling force, power and slip of the tandem cold rolling
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Xia, J.S. | 2023

In this paper, an Artificial Neural Network (ANN) is used to investigate the influence of rolling parameters such as thickness reduction, inter-strand tension, rolling speed and friction on the rolling force, rolling power, and slip of tandem cold rolling. For this reason, the rolling power was derived for 195 various experiments through a series of observation tests. The network is trained and tested using real data collected from a practical tandem rolling line. The best topology of the ANN is determined by Broyden–Fletcher–Goldfarb–Shanno (BFGS) training algorithm and error, and nine neurons in the hidden layer had the best performance. The average of the training, testing, and validating correlation coefficients data sets are mentioned 0.947, 0.924, and 0.943, respectively. The obtained results show MSE value 4.2 × 10−4 for predicting slip. In addition, the effect of friction and angular velocity condition on the cold rolling critical slip phenomena are investigated. The results show that ANNs can accurately predict the cold rolling parameters considered in this study.

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Psychophysiological and psychosocial profile of patients attending drug addiction centers
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Clemente-Suárez, Vicente Javier | 2021-12-27

Drug treatment centres provide the highest level of rehab services for patients diagnosed with drug addictions. Most inpatient drug rehab programs focus on medical detox and mental health interventions. However, how to optimize the later remains a challenge. The aim of this study was to examine the psychophysiological and psychosocial profile of patients attending drug addiction centres in comparation with the general population. A total of 105 inpatient drug rehab patients and 50 participants from the general population were compared based on standardized psychophysiological and psychosocial measures. Results of this study suggest that patients attending drug addiction centers differ from general population in several different psychophysiological and psychosocial factors. Patients reported significantly lower levels of physical activity and increased sympathetic responsiveness, and significantly higher levels in loneliness, psychologically inflexibility and neuroticism. The results of this study highlight the importance of address healthy lifestyle behaviors such as sport practice and psychological variables such as loneliness, psychological (in)flexibility and neuroticism to improve current programs aim to prevent or reduce problematic drug consumptions.

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Twitter data mining for the diagnosis of leaks in drinking water distribution networks ﻿

Privacy preserving blockchain with energy aware clustering scheme for iot healthcare systems ﻿

Technologies for the preservation of cultural heritage—a systematic review of the literature ﻿

On the relation between monocultures and ecosystem services in the Global South: a review ﻿

On the influence of drained cyclic preloadings on the cyclic behaviour of Zbraslav sand ﻿

Influence of ambient temperature in the city of Portoviejo, Ecuador on the energy performance of photovoltaic modules ﻿

Green building's heat loss reduction analysis through two novel hybrid approaches ﻿

Exploitation of Bauhinia forficata residual fruit powder for the adsorption of cationic dyes ﻿

El patrimonio cultural inmueble como derecho colectivo. Consideraciones sobre su protección y conservación en Colombia. ﻿

Development and validation of a prototype for the on-line simultaneous analysis of quality caprolactam synthesized on an industrial scale ﻿

Designing multifunctional biocatalytic cascade system by multi-enzyme co-immobilization on biopolymers and nanostructured materials ﻿

Critical rare earth metal adsorption onto expanded vermiculite: accurate modeling through response surface methodology and machine learning techniques ﻿

Air pollution in central European capital (Budapest) via self-made passive samplers and Sentinel-3B SYN satellite images ﻿

A universal model of three-phase asynchronous motors for electrical power system analysis ﻿

Treatment of residual lubricating oil using rice husk-based material as ecological adsorbent ﻿

Neuropsychological effects and cognitive deficits associated with exposure to mercury and arsenic in children and adolescents of the Mojana region, Colombia ﻿

Conversion of foliar residues of Sansevieria trifasciata into adsorbents: dye adsorption in continuous and discontinuous systems ﻿

Sexual-specific disgust sensitivity mechanisms in homonegativity and transnegativity; the mediating role of right-wing authoritarianism (RWA) ﻿

Using feed-forward perceptron Artificial Neural Network (ANN) model to determine the rolling force, power and slip of the tandem cold rolling ﻿

Psychophysiological and psychosocial profile of patients attending drug addiction centers ﻿

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Artículos científicos

Twitter data mining for the diagnosis of leaks in drinking water distribution networks

Privacy preserving blockchain with energy aware clustering scheme for iot healthcare systems

Technologies for the preservation of cultural heritage—a systematic review of the literature

On the relation between monocultures and ecosystem services in the Global South: a review

On the influence of drained cyclic preloadings on the cyclic behaviour of Zbraslav sand

Influence of ambient temperature in the city of Portoviejo, Ecuador on the energy performance of photovoltaic modules

Green building's heat loss reduction analysis through two novel hybrid approaches

Exploitation of Bauhinia forficata residual fruit powder for the adsorption of cationic dyes

El patrimonio cultural inmueble como derecho colectivo. Consideraciones sobre su protección y conservación en Colombia.

Development and validation of a prototype for the on-line simultaneous analysis of quality caprolactam synthesized on an industrial scale

Designing multifunctional biocatalytic cascade system by multi-enzyme co-immobilization on biopolymers and nanostructured materials

Critical rare earth metal adsorption onto expanded vermiculite: accurate modeling through response surface methodology and machine learning techniques

Air pollution in central European capital (Budapest) via self-made passive samplers and Sentinel-3B SYN satellite images

A universal model of three-phase asynchronous motors for electrical power system analysis

Treatment of residual lubricating oil using rice husk-based material as ecological adsorbent

Neuropsychological effects and cognitive deficits associated with exposure to mercury and arsenic in children and adolescents of the Mojana region, Colombia

Conversion of foliar residues of Sansevieria trifasciata into adsorbents: dye adsorption in continuous and discontinuous systems

Sexual-specific disgust sensitivity mechanisms in homonegativity and transnegativity; the mediating role of right-wing authoritarianism (RWA)

Using feed-forward perceptron Artificial Neural Network (ANN) model to determine the rolling force, power and slip of the tandem cold rolling

Psychophysiological and psychosocial profile of patients attending drug addiction centers