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Este trabajo de investigación fue realizado por los estudiantes del pregrado de Administración Ambiental de la Universidad Tecnológica de Pereira (UTP) para optar al título de Administrador Ambiental, después de culminado el pensum académico ofertado por la Institución para los 10 semestres de estudio. A lo largo de este recorrido investigativo, se evidencia que la cultura ambiental no es un juego y que las instituciones educativas deberían tomarse en serio el tema del cambio climático y sus derivados, creando una conciencia ambiental desde los claustros académicos. Para el desarrollo de esta investigación se toma como referencia la I.E. Educativa La Bella, sede La Cachucha, como objeto de estudio; Esta institución cuenta con 6 sedes a lo largo del corregimiento La Bella en el Municipio de Pereira, sector rural; esta institución en su sede principal, La Cachucha cuenta con un aproximado de 198 estudiantes y sus otras sedes suman un aproximado de 302 estudiantes, para un total de 500. Esta propuesta de educación ambiental se desarrolla a través de una cartilla que toma como referente 4 teras fundamentales para el ambiente: ciclo del agua, biodiversidad, suelos y aire. Temas que se desarrollaron con el docente de ciencias Naturales y los estudiantes del semillero de investigación que se formó con estudiantes de 6to a 8vo de la misma Institución, y los estudiantes del pregrado de Administración ambiental. La metodología con la que se desarrolló está investigación fue de tipo cualitativa, y se le dio un enfoque desde lo descriptivo, lo explicativo y lo propositivo para llevar a cabo los objetivos planteados, realizando recolección de datos, análisis y trabajo grupal., This research work was carried out by the students of Environmental Administration undergraduate program of the Universidad Tecnológica de Pereira (UTP) to opt for the degree of Environmental Administrator, after completing the academic curriculum offered by the Institution for the 10 semesters of study.Throughout this research, it is evident that environmental culture is not a game and that educational institutions should take seriously the issue of climate change and its derivatives, creating an environmental awareness from the academic cloisters. For the development of this research, the I.E. Educativa La Bella, La Cachucha, is taken as the object of study; this institution has 6 sites along the township of La Bella in the Municipality of Pereira, rural sector; this institution in its main site, La Cachucha has approximately 198 students and its other sites add up to approximately 302 students, for a total of 500.This environmental education proposal is developed through a booklet that takes as a reference 4 fundamental themes for the environment: water cycle, biodiversity, soil and air. air. These topics were developed with the Natural Sciences teacher and the students of the research group that was formed with students from 6th to 8th grade of the same Institution, and the students of the Environmental Administration undergraduate program. The methodology used to develop this research was qualitative, with a descriptive, explanatory and propositive approach to achieve the objectives set, through data collection, analysis and group work.

Debt and dispossession are two defining features of economic relationships in late-medieval Europe. This paper focusses on Vélez-Málaga (Málaga province) between 1487–1523, that is, the first years of the colonies founded after the Christian conquest. It studies the dispossessions enacted by the third count of Cabra during two periods of high inflation and the effects of his actions on the different social strata of Vélez’s settlers. Analysing both published (the repartimientos) and unpublished (that mainly proceed from the section of the House of Luque at the Archivo Histórico de la Nobleza from Toledo) documents, it concludes that, in the first years of its existence, the colonial society of Vélez-Málaga suffered a process of proletarianization that destroyed the community of small- and medium-scale landholders that had been created from the original distribution of indigenous property., El endeudamiento y la desposesión son dos de los elementos definitorios de las relaciones económicas de la Baja Edad Media en Andalucía, proceso en el que los episodios de crisis frumentarias jugaban un papel fundamental. Esta investigación se centra en el caso concreto de Vélez-Málaga (provincia de Málaga) entre los años 1487 y 1523, los primeros de la comunidad colonial que surgió de la conquista cristiana, y estudia la acción desposeedora del III conde de Cabra en el marco de dos periodos prolongados de subidas de precios, así como los efectos de su actuación en los diferentes estratos sociales de la población veleña. Se parte del análisis de documentación tanto inédita (procedente principalmente del fondo de la casa de Luque del Archivo Histórico de la Nobleza de Toledo) como publicada (los repartimientos) para concluir que, en las primeras décadas de su existencia, la sociedad colonial veleña sufrió un proceso de proletarización que desintegró la comunidad de pequeños y medianos propietarios surgida de los repartimientos.

The pose estimation of a surgical instrument is a common problem in the new needs of medical science. Many instrument tracking methods use markers with a known geometry that allows for solving the instrument pose as detected by a camera. However, marker occlusion happens, and it hinders correct pose estimation. In this work, we propose an adaptable multi-target attachment with ArUco markers to solve occlusion problems on tracking a medical instrument like an ultrasound probe or a scalpel. Our multi-target system allows for precise and redundant real-time pose estimation implemented in OpenCV. Encouraging results show that the multi-target device may prove useful in the clinical setting. © 2021, Springer Nature Switzerland AG.

We generate synthetic images with a generative adversarial network (GAN) model trained with image patches from specular microscopy corneal endothelial cells. Preliminary results show it may be a suitable approach for reliable cell segmentation. © 2022 The Author(s)

The investigation, and ultimate application, of topological insulators, typically involve exposure to ambient conditions or their integration with metals, which lead to surface oxidation or material intermixing. X-ray photoelectron spectroscopy (XPS) measurements that demonstrate passivated and intermixing-free interfaces in the topological insulator BiTe by means of dry-transferred CVD graphene are reported. After air exposure, no traces of BiTe oxidation are found. Furthermore, it is demonstrated that graphene acts as a very efficient metal and chalcogen diffusion barrier in BiTe/graphene/permalloy (Py) heterostructures, which are relevant for spintronics. Such results are in stark contrast with the significant surface degradation observed in bare BiTe under ambient conditions and the deep Bi-Te bonding disruption that occurs in BiTe/Py heterostructures. These findings provide a new approach to control and engineer topological insulator interfaces for spintronic applications and a new platform to investigate the combined use of graphene and topological insulator Dirac states.

Physiological human fluid is a natural corrosive environment and can lead to serious corrosion and mechanical damages to light Mg–Al alloys used in prosthetics for biomedical applications. In this work, organic–inorganic hybrid coatings doped with various environmentally friendly and non-toxic corrosion inhibitors have been prepared by the sol-gel process for the corrosion protection of AZ61 magnesium alloys. Effectiveness has been evaluated by pH measurements, optical microscopy, and SEM during a standard corrosion test in a Hanks’ Balanced Salt Solution. The results showed that the addition of an inhibitor to the sol-gel coating can improve significantly the corrosion performance, being an excellent barrier for the L-cysteine-doped hybrid sol-gel films. The incorporation of TiO nanoparticles, 2-Aminopyridine and quinine organic molecules slowed down the corrosion rate of the Mg–Al alloy. Graphene oxide seemed to have the same response to corrosion as the hybrid sol-gel coating without inhibitors.

The deposition of bioactive hydroxyapatite (HAp) coatings on pure magnesium (Mg) surfaces was studied. A modification of the biomimetic deposition method was used, which consisted in the incorporation of a supersaturated calcification solution (SCS). Different preparation parameters were modulated to obtain HAp and/or doped apatite coatings with different characteristics. The influence of the surface pre-treatments and soaking time in SCS on the physicochemical properties and the corrosion performance of the biomimetic HAp coatings were evaluated. Two different pre-treatments were explored to condition the sample's surface for the biomimetic HAp deposition. After the surface pre-treatments, the Mg samples were covered with HAp coatings by soaking in SCS during two immersion periods specifically chosen for this study: 2 h and 6 h, respectively. Scanning electron microscopy, coupled with energy-dispersive X-ray spectroscopy (SEM/EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Raman Spectroscopy, and Fourier transform infrared (FTIR), were applied for the chemical, morphological, and structural characterization of the resulting biomimetic HAp-coatings. The in vitro corrosion behavior was studied by open circuit potential (OCP) measurements and electrochemical impedance spectroscopy (EIS) during immersion tests in Ringer's physiological solution for up to 14 days. The results showed that HAp coatings were successfully deposited on the pure Mg substrates. Furthermore, the corrosion studies in Ringer's solution showed that HAp coating behavior depends not only on the pre-treatment type but also on the immersion time in SCS. These results open the door to propose different strategies to control—on demand—the corrosion rate of Mg coated with biomimetic HAp. These systems could be a promising alternative for designing and developing new temporary implants for the human body.

The ability to control the generation of spins in arbitrary directions is a long-sought goal in spintronics. Charge to spin interconversion (CSI) phenomena depend strongly on symmetry. Systems with reduced crystal symmetry allow anisotropic CSI with unconventional components, where charge and spin currents and the spin polarization are not mutually perpendicular to each other. Here, we demonstrate experimentally that the CSI in graphene-WTe induces spins with components in all three spatial directions. By performing multi-terminal nonlocal spin precession experiments, with specific magnetic fields orientations, we discuss how to disentangle the CSI from the spin Hall and inverse spin galvanic effects.

State-of-the-art fabrication and characterisation techniques have been employed to measure the thermal conductivity of suspended, single-crystalline MoS2 and MoS2/hBN heterostructures. Two-laser Raman scattering thermometry was used combined with real time measurements of the absorbed laser power. Measurements on MoS2 layers with thicknesses of 5 and 14 nm exhibit thermal conductivity in the range between 12 Wm-1 K-1 and 24 Wm-1 K-1. Additionally, after determining the thermal conductivity of the latter MoS2 sample, an hBN flake was transferred onto it and the effective thermal conductivity of the heterostructure was subsequently measured. Remarkably, despite that the thickness of the hBN layer was less than a hal of the thickness of the MoS2 layer, the heterostructure showed an almost eight-fold increase in the thermal conductivity, being able to dissipate more than ten times the laser power without any visible sign of damage. These results are consistent with a high thermal interface conductance G between MoS2 and hBN and an efficient in-plane heat spreading driven by hBN. Indeed, we estimate G ∼ 70 MW m-2 K-1 for hBN layer thermal conductivity of 450 Wm-1 K-1 which is significantly higher than previously reported values. Our work therefore demonstrates that the insertion of hBN layers in potential MoS2-based devices holds the promise for efficient thermal management.