Escuela Colombiana de Carreras Industriales

Dengue remains a major public health challenge in Colombia, with Valle del Cauca experiencing recurrent outbreaks characterized by seasonal fluctuations and long-term variability. Understanding the transmission dynamics of Dengue across age groups is critical for targeted interventions. In this study, we developed an age-structured stochastic host-vector model, incorporating a compartmental SIR-SI framework within a stochastic differential equation (SDE) approach. The population is stratified into youths (0-17 years) and adults (18 years and older), enabling analysis of age-specific infection and recovery patterns. Simulations and forecasts were performed using the Euler-Maruyama method, informed by fixed parameters from the literature, estimated disease-specific parameters, and epidemiological data from Colombia's Public Health Surveillance System (SIVIGILA) spanning 2013-2023. Additionally, a Seasonal Autoregressive Integrated Moving Average (SARIMA) model was employed as a complementary approach to capture and forecast monthly Dengue incidence. Our results highlighted distinct epidemic patterns across age groups, the higher infection burden among adults, and the complementary roles of mechanistic SDE modeling and SARIMA forecasting for surveillance and control planning.

Abstract Colombia is the only country that supports populations of three tapir species. Among them, the mountain tapir ( Tapirus pinchaque ) is classified as Endangered (EN) due to the rapid transformation of its natural habitats. This threat is further exacerbated by climate change, which facilitates the upward migration of parasites, putting additional pressure on the species. Currently, the mountain tapir faces a critical threat from mortality caused by myiasis, presumably induced by cattle screwworm flies. To date, nine confirmed cases of fatal myiasis have been reported during the last 3 years in the south-western region of the country on the central mountain range of the Andes: eight in Otún Quimbaya, Risaralda, and one in Peñas Blancas, Calarcá, Quindío, influence area of Los Nevados Natural National Park, recognized strongholds for the species’ conservation in the country. Current population estimates suggest fewer than 100 individuals remain in the area of the park, raising significant concerns about the long-term viability of the species. As a signatory to the COP 16 agreements held in Cali in 2024, Colombia committed to adopting the “One Health” approach as part of its National Biodiversity Plan under the Kunming-Montreal Framework. This approach aims to address the interconnectedness of biodiversity and health through an integrated, holistic perspective. In this study, we propose a One Health-based strategy to mitigate the potential risk of local extinction of the mountain tapir in this zone of epizootic events. Our methodology integrates geographic information system (GIS) analyses and mathematical modeling to examine the demographic impact of screwworm myiasis on T. pinchaque . We developed a situational analysis focused on a multisectoral response plan and advocate for the urgent implementation of contingency measures to ensure mountain tapirs’ survival and slow down the ongoing process of local extinction. We conclude that environmental surveillance through community participatory science, combined with social sensors detecting unusual natural behaviors, can complement the efforts of environmental decision makers, academic researchers, and productive sector stakeholders. Moreover, species conservation, particularly extinction prevention, is only achievable through the integration of capacities across multiple sectors, breaking down traditional silos. One Health impact statement We consider this work highly relevant within a One Health context, as it analyzes and provides management tools and information to address the urgent threat of extinction facing the mountain tapir. This ecologically vital species is at risk due to a human-induced epidemic associated with myiasis caused by cattle screwworms. The issue involves the interconnected health of humans, animals, and the environment, requiring a holistic, multistakeholder, and transdisciplinary approach to foster integration across different sectors within the One Health framework. We conclude that species conservation, particularly extinction prevention, is only possible through the integration of capacities across multiple sectors, breaking down traditional silos. Environmental surveillance through community participatory science, along with the use of social sensors to detect unusual natural behaviors, can complement the efforts of environmental decision makers, academic researchers, and stakeholders in the productive sector. These groups are both primary contributors to and beneficiaries of the proposed conservation strategy.

Filoviruses are enveloped, non-segmented, negative-strand RNA viruses belonging to the Filoviridae family, which includes five genera: Ebolavirus, Marburgvirus, Cuevavirus, Striavirus, and Thamnovirus. Members of this family cause severe and, often, fatal hemorrhagic fevers in humans and non-human primates, with high mortality rates. To date, only two filoviruses, Ebola virus (EBOV) and Marburg virus (MARV), are known to infect humans and are listed as priority pathogens by the World Health Organization due to their potential for re-emergence and the current lack of effective vaccines and antiviral treatments. In this study, we identify and characterize conserved binding sites within key filoviral proteins to support the development of broad-spectrum, direct-acting antiviral agents. We validated the significance of these conserved regions for drug discovery using existing experimental data. Our analysis revealed notably high sequence similarity among proteins from filoviruses capable of infecting humans (EBOV, TAFV, BDBV, SUDV, MARV, and RAVV) compared to those from non-zoonotic species, with the highest conservation observed in the L and VP40 proteins—both critical for viral genome transcription and replication. Furthermore, we compiled and analyzed available experimental data on known antiviral compounds targeting these proteins, identifying several agents with cross-filovirus activity, including Galidesivir, Remdesivir, and Favipiravir. The integrated approach described here—combining sequence and structural conservation analysis with chemical structure and antiviral activity data—demonstrates a strategy that could be extended to the development of broad-spectrum therapeutics across multiple viral families.

This study investigates the development of silver (Ag)-doped zirconia (ZrO2) coatings deposited on 316LVM stainless steel via the unbalanced magnetron sputtering technique. The oxygen content in the Ar/O2 gas mixture was systematically varied (12.5%, 25%, 37.5%, and 50%) to assess its influence on the resulting coating properties. In response to the growing demand for biomedical implants with improved durability and biocompatibility, the objective was to develop coatings that enhance both wear and corrosion resistance in physiological environments. The effects of silver incorporation and oxygen concentration on the structural, tribological, and electrochemical behavior of the coatings were systematically analyzed. X-ray diffraction (XRD) was employed to identify crystalline phases, while atomic force microscopy (AFM) was used to characterize surface topography prior to wear testing. Wear resistance was evaluated using a ball-on-plane tribometer under simulated prosthetic motion, applying a 5 N load with a bone pin as the counter body. Corrosion resistance was assessed through electrochemical impedance spectroscopy (EIS) in a physiological solution. Additionally, tribocorrosive performance was investigated by coupling tribological and electrochemical tests in Ringer’s lactate solution, simulating dynamic in vivo contact conditions. The results demonstrate that Ag doping, combined with increased oxygen content in the sputtering atmosphere, significantly improves both wear and corrosion resistance. Notably, the ZrO2-Ag coating deposited with 50% O2 exhibited the lowest wear volume (0.086 mm3) and a minimum coefficient of friction (0.0043) under a 5 N load. This same coating also displayed superior electrochemical performance, with the highest charge transfer resistance (38.83 kΩ·cm2) and the lowest corrosion current density (3.32 × 10−8 A/cm2). These findings confirm the high structural integrity and outstanding tribocorrosive behavior of the coating, highlighting its potential for application in biomedical implant technology.

El efecto de las redes sociales en el consumo ha sido abordado en diferentes contextos, por lo tanto, el objetivo de esta investigación es analizar si el contexto cultural en redes sociales, la autoestima personal y la apreciación corporal influyen en la aceptación e intención de práctica de una cirugía estética en mujeres centennials. Para esto se aplicó un cuestionario a 389 mujeres entre los 18 y 27 años de la ciudad de Bogotá, y para validar las hipótesis se utilizó un modelo de ecuaciones estructurales. Los resultados sugieren que tanto la autoestima personal (ap) como la imagen corporal (ic) no inciden en la percepción y aceptación a practicarse cirugías estéticas (acss); sin embargo, las actitudes socioculturales de los medios de comunicación (asc) sí influyen en esto, así como también influyen en la autoestima personal (ap) cuando es mediada por la imagen corporal (ic). De esta forma, las mujeres de la generación centennial o Z aceptan practicarse cirugías estéticas por efecto del contexto social y cultural en redes sociales, mas no por una baja autoestima o imagen corporal.

Abstract In this paper, we explore classical electromagnetic radiation using a dual four-dimensional potential Θ μ approach. Our focus is on the Planar Dipole Blade Antenna (PDBA), a system consisting of two flat perfect conductive regions on the xy-plane, separated by a gap G , with alternating potentials applied to the conductors. This method emphasizes the use of the scalar magnetic potential Ψ( r , t) and the electric vector potential Θ , which generates the electric field E ( r , t) = ∇ × Θ ( r , t) in free space. These potentials replace the standard magnetic vector potential A and the scalar electric potential Φ in our analysis. For harmonic radiation, the electromagnetic field can be expressed in terms of the electric vector potential Θ ( r , t). We derive a corresponding retarded vector potential for Θ in terms of a two-dimensional vector field W( r , t), which flows through the gap region G . This dual analytical approach yields mathematically equivalent expressions for modeling Planar Blade Antennas, analogous to those used for ribbons in the region G , simplifying the mathematical problem. In the gapless limit, this approach reduces the two-dimensional radiator (PDBA) to a one-dimensional wire-loop-like antenna, significantly simplifying the problem's dimensionality. This leads to a dual version of Jefimenko's equations for the electric field, where W behaves like a surface current in the gap region and satisfies a continuity condition. To demonstrate the utility of this approach, we provide an analytical solution for a PDBA with a thin annular gap at low frequency.

En el entorno competitivo actual, la gestión integral de la cadena de suministro se convierte en un factor clave para el éxito empresarial, sin embargo, desconocer cómo podría estar constituida de manera óptima se convierte en un problema que condiciona la operación en las organizaciones. Varios son los elementos que permiten identificar el funcionamiento de la logística al interior de las empresas, sin embargo en el presente documento se plantea caracterizar la operación de la fase de aprovisionamiento para la gestión de inventarios en el servicio de mantenimiento automotriz en TALLERES EL NORTE a partir de la alineación del plan de mejoramiento o de acción con el modelo SCOR, el cual, es sin duda uno de los referentes actuales mejor calificados en los esquemas de expansión estratégica en los nichos de mercado.Por tanto, en este proyecto de investigación interinstitucional, se caracteriza la operación de la fase de aprovisionamiento para la gestión de inventarios buscando una expansión del mercado PYME, en donde los aportes teóricos son favorables para dimensionar el impacto que genera la buena aplicación del proceso durante toda la cadena de suministro interna de la propia organización; así mismo se espera que, el proyecto genere aportes significativos en materia exploratoria para ambas universidades a partir de sus investigadores, mediante las actividades que se desarrollan durante el proceso académico pueden ser elevadas en participaciones de carácter internacional en el entorno de la Industria 4.0.

The stepper motor has been highlighted as a key component to achieve controlled and precise movements. This article focuses on the design and development of a stepper motor control system, with a subsequent application on a crane that will lift a small mass vertically. Each single aspect of the process has been examined in detail: from the selection and configuration of the 28BYJ-48 motor, to the implementation of the interfaces control such as the 4x4 matrix keypad and RS232 communication. In this system the control resides on the PIC18F4550 microcontroller. The control approach has had two modes: manual and automatic. In manual mode, the matrix keyboard has been used to allow direct interaction with the crane, adjusting parameters such as speed or direction. The automatic mode has demonstrated the ability to perform predefined movements, with a specific number of steps that ensure positioning accuracy. Overall, present study shows a comprehensive electronic control system, offering applicability in various technological areas. As research in this field progresses, this system provides a solid foundation for future improvements and optimizations in similar systems.