Universidad Tecnológica de Bolívar
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Abundance and distribution of cigarette butts on the sand of five touristic beaches in Latin America during the COVID-19 pandemic
No full textCigarette butts (CB) and cigarette butt fibers (CBF) are highly abundant and frequent residues on beach sand.
Also, they are hazardous waste due to their significant toxicity and potential risk to the ecosystems’ biota and the
health of beach tourists. This study aimed to determine the abundance and density of CB and CBF found on the
active, rest, and service zones of five pilot beaches in Argentina, Colombia, Brazil, Ecuador, and Mexico. The
methodology involved collecting CB and CBF in 500 m2 transects of urban tourist beaches using a citizen scienceadapted
methodology between June 2021 and May 2022, during the COVID-19 pandemic. The abundance and
density of CB and CBF, and the Cigarette Butt Pollution Index (CBPI) were calculated. The highest proportion of
CB was found in service and rest areas. Bocagrande (CO) reported the highest generation of CB and CBF and a
severe CBPI.APCs y acuerdos transformativos 2023, Elsevie
MALDI-TOF MS for the identification of bacteria from Acropora cervicornis samples with White Band Disease
No full textWhite Band Disease (WBD) is one of the most harmful coral syndromes in the Caribbean, deteriorating the structure of many corals during the eighties and nineties. Since its etiology is not entirely known, the use of techniques aimed a t identifying the associated agents could provide an approach to the composition of the populations involved in the deterioration of A. cervicornis. Therefore, this research's objective was to isolate and characterize bacteria associated with WBD in A. cervicornis from hanging nurseries of Rosario and San Bernardo Corals National Natural Park, Colombia, using MALDI-TO F MS and PCR. The results showed the presence of Bacillus cereus bacteria in individuals with bleaching signs from nurseries and transplant areas on Isla Tesoro and Isla Ceiner. One of these strains sequenced and phylogenetically analyzed was closely related t o Bacillus thuringiensis, with similarities of up to 99%. The presence of B. cereus could indicate a special relationship between this microorganism and WBD. However, it is imperative to carry out more studies on identifying the bacteria associated with this disease to support these findings. © 2022 Latin American and Caribbean Consortium of Engineering Institutions. All rights reserved
Extended focused image in white light scanning interference microscopy
No full textWe propose a method to obtain a fringe-free extended focused image in white light scanning interference microscopy based on processing the stack of images over a range within the coherence length of the source. © 2019 The Author(s)
Sistema de Control para la Gerencia de Proyectos en una Compañía del Sector de la Construcción a través la Técnica del Valor Ganado en el Caribe
No full textThe present research work generates a solution to some inconveniences presented in an organization that executes construction projects, which has presented problems of delays in the works, cost overruns in the activities and reduction of the scope of the projects, for this reason it is carried out an analysis of the bibliography related to project management systems based on the earned value methodology and through documentary observation. Through an information collection tool, a diagnosis of the object of study was made, and it was extended to the construction sector of the Colombian Atlantic Coast with the objective of having regional trends. With the analysis of the results obtained, a project management system was proposed based on some of the organizational strengths that the company has. The design and implementation of this system are intended to improve the success of projects in terms of cost, duration a nd scope. © 2022 Latin American and Caribbean Consortium of Engineering Institutions. All rights reserved
Difusión digital de objetos: Expresiones culturales y turísticas en colombia
No full textThe objects and cultural expressions are part of the representative tourism of the regions, therefore, this article aims to demonstrate the visibility of them digitally assisted with technological tools supported by Information and Communication Technologies. Methodologically, the study was framed in the qualitative approach with a type of descriptive-documentary research based on the tourist cultural inventory of the department of Sucre, Colombia of the year 2020. The categorization of artistic expressions, specifically living pictures, were made from a semi-structured interview applied to Key informants, likewise, information was collected through documentary review and photographic records of some objects, cultural-tourism techniques. Diversity of expressions that represent the Sucre subregions were identified, as well as interesting attractions for national and foreign tourists. However, depending on the technological development, a modeling for their digital diffusion is specified, such as augmented reality with a GPS system, involving the expressions of living pictures, the innate traditional gastronomy such as the cheese nickname, the crafts with braiding. cane arrow like the internationally renowned vueltiao hat. It is suggested to inquire in the future about cultural sensitivity based on the use of ICT. © 2021, Universidad del Zulia. All rights reserved
Love Thy Neighbor: La Vida Musical De Justo Almario
No full textSegún Licho Almario, en vista del talento y la musicalidad de Justico, el italiano Antonio
Testoni le regaló un clarinete en Bb, y luego Adolfo Podestá le regaló un saxofón, e incluso Lucho Bermúdez le regaló una boquilla, y otro italiano, Gualtiero Barbieri, le mandaba a comprar libros de música en Italia.
“Yo vivía muy cerca del Club Medellín, donde yo trabajaba de planta con la orquesta Italian Jazz. Entonces Justo tocaba el flautín o lo que le llaman pícolo. Entonces los músicos de la orquesta eran feliz porque en esa época no era sino una sola
orquesta y el público siempre acosaba: “¡que toquen, que toquen!”, cada rato que toquen, que la orquesta siguiera. Entonces yo me llevaba a Justo y Justo con el flautín hacía los intermedios”
Spatio Temporal Filtering of Multi-lead ECG Signals for Atrial Arrhythmia Classification
No full textAtrial fibrillation (AF) is the most common cardiac arrhythmia and increases the risk of suffering stroke. Some people with AF do not have symptoms, so, its diagnosis can be difficult, especially in early stages of the disease. In this paper, we propose the use of the spatio-Temporal filter (STF) to characterize atrial activity in ECG recordings and distinguish between normal sinus rhythm (NSR) and atrial arrhythmias. This method allows the effective detection of P waves when they are synchronized with QRS complexes. The distances from the QRS complexes to the detected P waves are characterized by seven dispersion metrics that are used as inputs to three clustering algorithms. The results show classification accuracy of up to 98.88% of NSR and atrial arrhythmias
Applying a Green Solvent with Microwave, Ultrasound, and Soxhlet Extraction Techniques to Quantify the Slip Additive Cis-1,3-docosenamide and Nine Oxidative Degradation Byproducts in Polypropylene Samples
No full textErucamide is used as an important slip agent for polymers. However, erucamide can
degrade during processing and long-term storage, forming various oxidation products. These degra dation products can affect the recovery rates of erucamide. In this study, investigated different
solid–liquid extraction methods (Soxhlet, microwave, and ultrasound) and used gas chromatography
with mass spectrometry (GC-MS) to quantify erucamide and its degradation byproducts in polypropy lene (PP). A multivariable experiment was designed, and a mixed-effect approach was used to analyze
the results. Various extraction variables were examined, such as temperature, time, solvents, and PP
pretreatments. Using a mixed-effect model with a Kenward–Roger approximation, an R2 of the model
of 97% and p values of 0.168, 0.000, and 0.000 were obtained for the technical, solvent, and type of PP
pretreatment variables, respectively. The highest average recoveries of erucamide were found with
the microwave technique and were 96.4% using dichloromethane, 94.57% using cyclohexane, and
93.05% using limonene. With ultrasound, recoveries ranged between 85 and 92% for dichloromethane
and limonene. In addition, it was observed that the extraction method had better recovery results in
ground PP than in films and in pellets. Nine oxidative degradation byproducts of erucamide were
identified and semi-quantified by GC-MS. The reaction mechanisms for forming each byproduct
were proposed. The byproducts that experienced a higher rate of degradation of erucamide were
erucamide with a hydroxyl group at position one and 12-amino-6-12-oxo-dodecanoic acid, showing
more prominent peaks using the Soxhlet method with cyclohexane and dichloromethane as solvents
and polypropylene (PP) films as the type of material used.Universidad Tecnológica de Bolivar, Universidad de Cartagena, Universidad de la Cost
[Estilos de aprendizaje, género y rendimiento académico en estudiantes del curso Fundamentos de Economía
No full textAcevedo Pierart, C. G., & Rocha Paves, F. (2011). Learning styles, gender and academic performance. Journal of Learning Styles, 4(8), 71-84.Objective. This article aimed to analyze the relationship between learning styles, gender, and students’ academic performance in the Fundamentals of Economics course at the Universidad Tecnológica de Bolívar (UTB). Methodology. The study used a quantitative approach with a descriptive-correlational research design. It administered the Honey-Alonso Learning Style Questionnaire (CHAEA) to 166 students. The data was processed with the Stata (version 13.0) statistical package for Windows. Two models were designed and applied to establish correlations and probability: a linear probability model and a probabilistic probit model. Results. Statistical significance is evident at 10% with respect to the preferences of active and reflective styles. Similarly, there is a possible association between the preference for reflective style and the increased chances for students to pass the course. Conversely, the probability of passing the course is lower when the preference is for the active style. Conclusion: The study evidenced the relationship between gender and pragmatic learning style. It also showed that students with preferences for the reflective learning style have a higher probability of improving their academic performance in the Fundamentals of Economics course. In addition, those who prefer the active learning style are less likely to enhance their academic performance. © 2023 Universidad Nacional. All rights reserved
Nuevos escenarios, actores y prácticas educativas donde se construye la convivencia, la diversidad y la cultura
No full textIntroduction. Colombia has a variety of territories, people, cultures, political, and religious affiliations; however, it has been affected by a history of violence, inequality, corruption, among other evils, associated with the lack of tolerance for differences and the lack of protection for communities and minorities. Objective. The study was proposed to unveil the knowledge produced by organizations, their cultural modes of knowledge construction, intercultural learning, practices, and knowledge. As a counter-hegemonic bet, it was proposed to make them visible by considering their territories, life stories, and experiences. Method. The study was conducted from participatory action research, with 38 co-researchers from 13 organizations through pedagogical/research meetings, visits to territories, reflection circles, and interviews. Results. The study identified lines of flight analyzed from the perspective of the decolonization of aesthetic, epistemic manifestations, and the configuration of pedagogy in a territory as a vehicle of relations, the care of oneself and others in common spaces from dialogues, and plurilogical and multicultural practices. Conclusions. It is possible to demonstrate the recognition of an epistemic diversity and another pedagogy, that is, a call for other logics/rupture of the unitary idea of the world. Within the educational process of organizations, it is also possible to find paths to educate differentials, where educational concepts and methods are removed from the past and presented as everyday events that are interrogated in deliberative spaces. © 2022 Universidad Nacional. All rights reserved