A multi-country test of brief reappraisal interventions on emotions during the COVID-19 pandemic.

The COVID-19 pandemic has increased negative emotions and decreased positive emotions globally. Left unchecked, these emotional changes might have a wide array of adverse impacts. To reduce negative emotions and increase positive emotions, we tested the effectiveness of reappraisal, an emotion-regulation strategy that modifies how one thinks about a situation. Participants from 87 countries and regions (n = 21,644) were randomly assigned to one of two brief reappraisal interventions (reconstrual or repurposing) or one of two control conditions (active or passive). Results revealed that both reappraisal interventions (vesus both control conditions) consistently reduced negative emotions and increased positive emotions across different measures. Reconstrual and repurposing interventions had similar effects. Importantly, planned exploratory analyses indicated that reappraisal interventions did not reduce intentions to practice preventive health behaviours. The findings demonstrate the viability of creating scalable, low-cost interventions for use around the world

Enhancement of Fatigue Life of Polylactic Acid Components through Post-Printing Heat Treatment

To reduce the carbon footprint of manufacturing processes, it is necessary to reduce the number of stages in the development process. To this end, integrating additive manufacturing processes with three-dimensional (3D) printing makes it possible to eliminate the need to use tooling for component manufacturing. Furthermore, using 3D printing allows the generation of complex models to optimize different components, reducing the development time and realizing lightweight structures that can be applied in different industries, such as the mobility industry. Printing process parameters have been studied to improve the mechanical properties of printed items. In this regard, although the failure of most structural components occurs under dynamic load, the majority of the evaluations are quasistatic. This work highlights an improvement in fatigue strength under dynamic loads in 3D-printed components through heat treatment. The fatigue resistance was improved regarding the number of cycles and the dispersion of results. This allows 3D-printed polylactic acid components to be structurally used, and increasing their reliability allows their evolution from a prototype to a functional component

A Comparative Analysis of the Tribological Behavior of Hard Layers Obtained by Three Different Hardened-Surface Processes on the Surface of AISI 4140 Steel

This work compares the tribological behavior of surface layers obtained by three different hardening processes. The layers were formed on the surface of AISI 4140 steel by applying three different thermochemical treatments. Wear resistance was evaluated using a standardized tribological machine for abrasive wear, according to the limits established by the ASTM G65 “Standard Test Method for Measuring Abrasion Using Dry Sand/Rubber Wheel Apparatus”. According to the results, the boride layers exhibited the highest wear resistance, as compared to nitrided and carburized layers. In contrast, the carburized layers presented the highest loss of volume. Scanning electron microscopy (SEM) was used to analyze the worn surfaces to examine the wear mechanisms. Abrasive wear was identified in all the samples, as the main abrasive wear mechanism. The mean values of the coefficient of friction (CoF) of the hardened surfaces were 0.39, 0.55, and 0.65 for carburizing, nitriding, and boriding samples, respectively, indicating that the wear process may not always be related to a low CoF. The results suggest that the highest hardness is normally associated with high wear resistance, but the coefficient of friction could be not directly related to the hardness of the materials. Finally, a statistical study demonstrates the random nature of the layers obtained by three different hardening processes

Proyecto de Tesis II - CI189 - 202101

DESCRIPCIÓN Curso de especialidad en la carrera de ingeniería civil de carácter teórico-práctico dirigido a los estudiantes del 10mo ciclo. El curso Proyecto de Tesis II busca que los estudiantes de Ingeniería Civil apliquen sus capacidades adquiridas durante todos sus estudios, en completar una investigación, que plantea resolver una problemática en una de las líneas de la carrera. Con la ayuda de un docente asesor especialista en el tema lograran redactar el informe de tesis al 100%, este informe será revisado por otro docente especialista que proporciona sugerencias de mejoras a la investigación. Por último, los estudiantes exponen ante un jurado especialista sus resultados quienes evalúan y también hacen sugerencia de mejoras a la investigación. PROPÓSITO En el Perú actualmente existe un gran número de estudiantes de Ingeniería Civil que no cuentan con el título profesional, por no realizar la tesis de investigación, lo cual disminuye significativamente su desarrollo profesional y sus oportunidades laborales. Adicionalmente las leyes Peruanas exigen que para el obtener el bachillerato los estudiantes deben redactar un trabajo de investigación. El curso de proyecto de Tesis 2 permite que los estudiantes puedan desarrollar el 100% de la Tesis y un trabajo de investigación, siendo ambos certificados por un asesor y un jurado evaluador. Este curso contribuye con el desarrollo de las competencias generales de comunicación escrita, comunicación oral, manejo de la información y ciudadanía y las competencias específicas 2, 3, 5 y 6 de ABET, todas a nivel de logro 3. Cuenta con el prerrequisito de Proyecto de Tesis 1