Due to the global alert about the risk of contagion and propagation of Covid-19, a situation that has changed in the educational processes, this has forced the system to migrate towards a more dynamic and connected model of teaching and learning, which has allowed not to interrupt and to continue with the training processes, in a remote and assisted way. In this research, the profile of the engineering and science student is analyzed, and its relationship with the learning of physics in this crisis. For this purpose, the technique of simple random sampling of a certain population was applied, a research instrument was designed and validated by pairs of experts, its reliability was established based on Cronbach’s Alpha test, and the instrument was applied to 354 students of the faculty of engineering and basic sciences, of the Universidad Francisco de Paula Santander, located in the city of Cúcuta, Colombia, during a 15-day time window, the analysis of the data and variables is carried out from the design of a mathematical model of logistic regression, where the dependent variable represents the feeling of emotional affect by the obligatory social isolation. The results indicated that the students feel emotionally affected in 88.56% generating implications in the learning of physics and in their academic performance, especially those who comply the profile: being female, single, not having received training in the use of digital platforms, without academic difficulties but who feel that their academic performance has been affected.

The present study aims to analyze the secondary movement of the piston considering the deformations present in the piston skirt, the hydrodynamic lubrication, and the effects of the clearances in the connecting rod bearings. The analysis of the piston movement is performed by developing a mathematical model, which was used to evaluate the dynamic characteristics of the piston movement, the slap force on the piston skirt, the effect of the secondary piston movement on the connecting rod, and the influence of clearances in the connecting rod bearings and in the piston. For the study, the geometric of the crankshaft-connecting rod–piston system of a single-cylinder diesel engine is taken as a reference. The deformation model of the piston was carried out by means of a symmetric finite element model (FEM), which was integrated into the mathematical model of the piston. MATLAB® software (The MathWorks Inc., Natick, MA, USA) is used for the development of model simulations. The obtained results show that during the combustion cycle, there are six changes of direction in the secondary movement of the piston with lateral and angular velocities that can reach a magnitude of 0.13 m/s and 4 rad/s. The lateral and angular movement of the piston during its travel causes the appearance of impacts on the piston skirt with the cylinder liner, which produces an increase of approximately 500 N in the hydrodynamic forces in the connecting rod bearings. The force analysis shows that the range of the maximum magnitudes of these forces is between 1900 N and 3480 N. The increase in clearance between the cylinder liner and the piston skirt (Cpc) causes a greater lateral displacement and an increase in the angle of inclination of the piston. Analysis of the change in connecting rod bearing clearance shows that there are critical values in relation to clearance Cpc. The model presented allows us to analyze the different characteristics of the secondary movement of the piston, which involve the interaction between the piston skirt and the cylinder liner. Additionally, the influence of this movement on the connecting rod bearings is considered. The foregoing can be used as an analysis tool for the study of designs and/or modifications in the engine in such a way that greater durability of the components, reductions in acoustic emissions, and reduction in friction losses are achieved.

In this research work, a description was made of thermoset polymer materials and their relationship with the environment. The traditional thermoset manufacturing processes make their recycling and reuse complicated. Consequently, most products made with this type of material end up accumulating in landfills and their disposal generates a high environmental impact. This is why a description of thermoset and biodegradable polymers is made to identify the differences between them and the advantages of biodegradable materials. This being so, it is found that the scientific community presents as a proposal or alternative solution to this environmental problem the development of new methodologies and technologies to synthesize families of thermoset biodegradable materials, as for example the case of “glycix”, “titan” and “hydro”, and that from capital investment in science and technology processes in the area of materials engineering, by the productive sector and Universities of countries such as for example; Mexico and Argentina, managed to develop on an industrial scale biodegradable resins that can be processed by all conventional plastic molding methods and significantly reduce the carbon footprint.

Las instituciones de educación superior tienen directa incidencia en el desarrollo de los países a través de un proceso continuo que apunta hacia la construcción de conocimientos para generar beneficios, calidad de vida en la población y desarrollo humano de los habitantes; escenario en el que a su vez, los profesionales de las diversas disciplinas son determinantes cuando se han beneficiado de una educación superior de alta calidad, en donde la economía del conocimiento ejerce un papel preponderante; precisión que ha dado lugar al presente artículo cuyo objetivo es   analizar   algunos   fundamentos    teóricos y metodológicos con base en resultados de algunas investigaciones anteriores relacionadas con la calidad educativa a nivel superior y con la economía del conocimiento. La metodología aplicada se basa en el enfoque cualitativo, desarrolla un tipo de investigación exploratoria de acuerdo con la   búsqueda   y   selección de fuentes secundarias de información que permitieron examinar resultados en esta materia y que están relacionados con las mejoras en la calidad educativa de parte de las instituciones de educación superior en los programas que ofrecen, destaca que en el Sistema Nacional de Información de la Educación Superior, SNIES existían 13.134 registros calificados activos, de los cuales 6.377 corresponden a programas de posgrados y 6.757 a programas académicos de pregrado; existe una concentración de la oferta de maestrías y en especial de doctorados en Bogotá, Medellín y Cali, pero también se identifica un número importante de estos programas en Manizales y Barranquilla. Como conclusión se señala que la evaluación de la calidad de los servicios educativos ofrecidos por la educación superior está relacionada con la acreditación ante el CNA.

In recent years, the popular term “polymer-drug conjugate” has been introduced to describe new drug targets to combat diseases such as cancer. Due to its potential benefits in terms of human health, this concept has managed to gain attention in the pharmaceutical industry. These innovative developments involve detailed processes in materials science, as it is required to encapsulate different types of cells, as an active component within a material that releases the drug or conjugate directly on the tumor or in the affected area. Against this backdrop, the main objective of this work is to explore the state of participation of polymeric materials in medical and pharmaceutical sciences, in a context where recent cancer statistics are provided in some countries. From the review of the literature, it is evident the importance of the synthesis of new materials or polymeric conjugates, because these materials at the beginning have been used only as storage and delivery systems of drugs, but today they are used as direct treatment against diseases such as cancer, that is, as bioactive agents. Finally, it is possible to conclude that the conjugated polymer-proteins or polymer-drugs, currently on the market and others in the clinical research phase, these materials present physical properties such as biocompatibility and biodegradability, that is, compatibility with the living organism.