Micro- and nanostructures of metal doped ZnO : synthesis and ordered growth on laser structured substrates

Tesis inédita de la Universidad Complutense de Madrid, Facultad de Ciencias Físicas, leída el 29-04-2022En el presente trabajo de investigación se aborda la síntesis de micro- y nanoestructuras de ZnO dopado con diferentes elementos metálicos con el fin de estudiar sus propiedades y potenciales aplicaciones en dispositivos optoelectrónicos y de fotocatálisis. A tal fin, se ha analizado también la posibilidad de controlar espacialmente su crecimiento selectivo sobre diversos tipos de sustratos previamente estructurados con pulsos láser ultracortos. El ZnO es un semiconductor de banda ancha perteneciente al grupo de óxidos conductores trasparentes (Transparent Conductive Oxides, TCOs) cuyas propiedades resultan de especial interés para distintas aplicaciones. Se sabe que el uso de dopantes adecuados permite modificar y potenciar de manera muy significativa algunas de sus propiedades, especialmente eléctricas, ópticas y luminiscentes. Es por ello por lo que se ha estudiado cómo influye el dopado con distintos metales alcalinos (Li, K) y de transición (Zr) en las propiedades de las micro- y nanoestructuras sintetizadas mediante el método vapor – sólido (VS).Esta técnica de crecimiento permite obtener estructuras con una muy buena calidad cristalina y no hace uso de catalizadores, lo cual evita la incorporación de impurezas no deseadas en las estructuras. Se han realizado diferentes ensayos decrecimiento encaminados a optimizar el proceso para cada dopante variando tanto las condiciones de los tratamientos térmicos como mediante el empleo de diferentes precursores y el uso de diferentes niveles de dopado. Estos ensayos se han retroalimentado mediante las diferentes técnicas de caracterización empleadas, de naturaleza morfológica, composicional, estructural y óptica...This research work is focused on the synthesis of micro- and nanostructures of ZnO doped with different metallic elements with the aim of assessing their properties and potential applications in optoelectronic and photocatalytic devices.To this end, the possibility of spatially controlling their selective growth on various types of substrates previously structured with ultrashort laser pulses has also been analysed.ZnO is a broadband semiconductor belonging to the group of transparen tconductive oxides (TCO´s) whose properties are of special interest for differentapplications. It is known that the use of suitable dopants makes it possible to very significantly modify and enhance some of its properties, especially electrical, optical and luminescent ones. This is the underlying reason for analysing how doping with different alkali (Li, K) and transition (Zr) metals influences the properties of micro- and nanostructures synthesized by the vapor-solid (VS) method. This growth technique allows to obtain structures with very good crystalline quality and does not use catalysts, which avoids the incorporation of unwanted impurities in the generated structures. Different tests have been carried out aimed at optimizing the growth process for each dopant, varying both the conditions of the thermal treatments, through the use of different precursors, and the use of different levels of doping. These tests have been fed back through the different characterization techniques used, of a morphological, compositional, structural and optical nature...Fac. de Ciencias FísicasTRUEunpu

Penetration of polymeric nanoparticles loaded with an HIV-1 inhibitor peptide derived from GB virus C in a vaginal mucosa model

Despite the great effort to decrease the HIV infectivity rate, current antiretroviral therapy has several weaknesses; poor bioavailability, development of drug resistance and poor ability to access tissues. However, molecules such as peptides have emerged as a new expectative to HIV eradication. The vaginal mucosa is the main spreading point of HIV. There are natural barriers such as the vaginal fluid which protects the vaginal epithelium from any foreign agents reaching it. This work has developed and characterized Nanoparticles (NPs) coated with glycol chitosan (GC), loaded with an HIV-1 inhibitor peptide (E2). In vitro release and ex vivo studies were carried out using the vaginal mucosa of swine and the peptide was determined by HPLC MS/MS validated method. Moreover, the peptide was labeled with 5(6)-carboxyfluoresceine and entrapped into the NPs to carried out in vivo studies and to evaluate the NPs penetration and toxicity in the vaginal mucosa of the swine. The mean size of the NPs, ξ and the loading percentage were fundamental features for to reach the vaginal tissue and to release the peptide within intercellular space. The obtained results suggesting that the fusion inhibitor peptides loaded into the NPs coated with GC might be a new way to fight the HIV-1, due to the formulation might reach the human epithelial mucosa and release peptide without any side effects

The influence of meaningful activities in the quality of life and functional autonomy of adults with intellectual disability: A prospective study during the COVID-19 pandemic

This manuscript was published by Wiley in Journal of Applied Research in Intellectual Disabilities on May 2023, available at doi: 10.1111/jar.13077.Background: The COVID-19 pandemic might negatively impact the quality of life and functional autonomy of Spanish adults with intellectual disability, and meaningful activities could prevent this negative progression. Methods: This is a prospective cohort study in Spanish adults with intellectual disability during the COVID-19 pandemic. Quality of life, functional autonomy and functional independence were measured. The meaningful activities studied were structured-leisure, community self-management, and occupational and physical activities. Results: Seventy-three participants were included in the study. Quality of life and functional autonomy significantly deteriorated during the COVID-19 pandemic (all p > .001). Greater participation in community self-management activities before COVID-19 was associated with less detriment to quality of life (ß = .312; p = .008), while greater participation in occupational and physical activities was associated with less detriment to the performance of instrumental activities (ß = .317; p = .016; and ß = .285; p = .030, respectively). Conclusion: People with intellectual disability living in residential homes experienced a decrease in their quality of life and functional autonomy during the COVID-19 pandemic. Their involvement in community self-management activities and physical and occupational activities before the pandemic had preventive effects on the detriment to the quality of life and functional autonomy.Vicerrectorado de Igualdad, Inclusi on y Sostenibilidad at the Universidad de Granad

Metabolic impairments caused by a “chemical cocktail” of DDE and selenium in mice using direct infusion triple quadrupole time of flight and gas chromatography mass spectrometry

Among organic contaminants, pesticides are one of the most important groups of chemicals due to their persistent character and toxicity. However, the biological systems are exposed to a complex environment in which the contaminants can interact in a synergistic/antagonistic fashion, and for this reason, the study of “chemical cocktails” is of great interest to fully understand the final biological effect. In this way, selenium is known for its antagonistic action against several toxicants. In this paper, metabolic impairments caused by the joint exposure of p,p′-dichloro diphenyl trichloroethane (DDE) and selenium (Se) have been issued for the first time. A metabolomic workflow was applied to mice fed DDE and DDE with Se diet, on the basis of the complementary use of two organic mass spectrometric techniques, combining direct infusion mass spectrometry (DI-ESI-QqQ-TOF MS) and gas chromatography–mass spectrometry (GC–MS). The results show a good classification between the studied groups caused by about 70 altered metabolites in the liver, kidney, or brain, including the pathways of energy metabolism, degradation of phospholipidic membrane, β-oxidation, and oxidative stress, which confirm the potential of combined metabolomic platforms in environmental studies.This work has been supported by projects CTM2015-67902-C2-1-P and PG2018-096608 B-C21 from the Spanish Ministry of Economy and Competitiveness and P12-FQM-0442 and B10-1657 from the Regional Ministry of Economy, Innovation, Science and Employment (Andalusian Government, Spain). G.R.-M. thanks the Spanish Ministry of Economy and Competitiveness for a PhD scholarship (BES-2013-064501). S.R.-A. thanks the Spanish Ministry of Economy and Competitiveness for a PhD scholarship (BES-2016-076364). Finally, the authors are grateful to FEDER (European Community) for financial support, Grant Nos. UNHU13-1E-1611 and UNHU15-CE-3140

Design, Characterization, and Biopharmaceutical Behavior of Nanoparticles Loaded with an HIV‑1 Fusion Inhibitor Peptide

New therapeutic alternatives to fight against the spread of HIV-1 are based on peptides designed to inhibit the early steps of HIV-1 fusion in target cells. However, drawbacks, such as bioavailability, short half-life, rapid clearance, and poor ability to cross the physiological barriers, make such peptides unattractive for the pharmaceutical industry. Here we developed, optimized, and characterized polymeric nanoparticles (NPs) coated with glycol chitosan to incorporate and release an HIV-1 fusion inhibitor peptide (E1) inside the vaginal mucosa. The NPs were prepared by a modified double emulsion method, and optimization was carried out by a factorial design. In vitro, ex vivo, and in vivo studies were carried out to evaluate the optimized formulation. The results indicate that the physicochemical features of these NPs enable them to incorporate and release HIV fusion inhibitor peptides to the vaginal mucosa before the fusion step takes place. KEYWORDS: GB virus C, HIV-1, fusion inhibitor peptide of HIV-1, polymeric nanoparticles, factorial design, permeation studie

Lectura de contexto y abordaje psicosocial desde los enfoques narrativos Bogotá.

En este documento se expone el acercamiento conceptual a los enfoques narrativos a partir de las lecturas de los cuatro relatos del libro: VOCES: Relatos de violencia y esperanza en Colombia, esto nos permitió acercarnos a historias de vida que nos contextualizan acerca de la realidades que existen en Colombia, realidades que nos relatan los aspectos más crudos del conflicto armado y la violencia que se ha manifestado en este país, a partir de ellos se realiza una actividad individual y una colectiva donde se escoge el relato de Edison Medina, quien era un soldado de las fuerzas armadas de Colombia y por arbitrariedad del ejercito él debe huir y se integra a las FARC, nos narra su vivencias y aprendizaje. A partir del caso anteriormente expuesto se hará un abordaje psicosocial imaginando que tenemos al protagonista para realizarle una entrevista esto por medio de la reflexión y formulación de preguntas que consideremos pertinentes y que aporten a la intervención, estas preguntas serán de carácter estratégicas, circulares y reflexivas, donde cada una se diseña desde el contexto que nos oriente a un acercamiento psicosocial ético y proactivo en la superación de las diversas circunstancias de victimización. Finalmente se presenta el caso Pandurí, donde cada integrante realiza un análisis para generar una reflexión en cuanto el abordaje que se le hará y así se propondrán tres estrategias de acompañamiento psicosocial, estas estrategias irán encaminadas hacia una reparación y apoyo que requieren las víctimas del conflicto por medio del acompañamiento durante todo el proceso de profesionales capacitados en estas actividades.This document exposes the conceptual approach to narrative approaches based on the readings of the four stories in the book: VOICES: Stories of violence and hope in Colombia, this allowed us to approach life stories that contextualize us about the realities that In Colombia there are realities that tell us about the crudest aspects of the armed conflict and the violence that has been manifested in this country. From them, an individual and a collective activity is carried out, where the story of Edison Medina, who was a Soldier of the armed forces of Colombia and by arbitrariness of the army he must flee and join the FARC, he tells us his experiences and learning. Based on the previously mentioned case, a psychosocial approach will be made, imagining that we have the protagonist to interview him through reflection and formulation of questions that we consider pertinent and that contribute to the intervention, these questions will be strategic, circular and reflective. , where each one is designed from the context that guides us to an ethical and proactive psychosocial approach in overcoming the diverse circumstances of victimization. Finally, the Pandurí case is presented, where each member carries out an analysis to generate a reflection on the approach to be made and so three strategies of psychosocial accompaniment will be proposed, these strategies will be aimed at a repair and support required by the victims of the conflict through the accompaniment throughout the process of professionals trained in these activities

Morphology, Luminescence, and Optical Properties of Tb‐ and Li‐Codoped ZnO Elongated Nano‐ and Microstructures

A variety of morphologies of ZnO elongated nano- and microstructures doped with Li and Tb are obtained by a vapor–solid method. The amount of Tb incorporated depends on the morphology which is controlled by the amount of Li in the initial mixture and the growth conditions. X-ray diffraction and Raman experiments show the good crystalline quality of the samples. A small quantity of Tb3+ ions seems to be present in the structures, as both cathodoluminescence and photoluminescence suggest. The intensity of the ZnO and Tb3+ intrashell emission bands is strongly influenced by the amount of Li due to the different positions that it can occupy in the ZnO lattice. This fact leads to variations in the defect structure that change the concentration of native defects and the rare earth surroundings. The elongated structures also show waveguiding behavior and Fabry–Perot optical resonant modes with good quality factor

Evolution of whispering gallery modes in Li-doped ZnO hexagonal micro- and nanostructures

The investigated materials have great potential for integrated optoelectronic devices. The possibility to integrate them into the same material as optical resonator and light guide opens the door to the fabrication of highly compact devices. The formation of optical cavities in Li-doped ZnO nanostructures was investigated. By means of the vapor-solid method, long micro- and nanostructures with a hexagonal cross-section were grown. These morphologies were favorable for Fabry-Perot and whispering gallery modes to appear. A variety of structures with different sections was studied using mu-photoluminescence in both the transverse electric (TE) and transverse magnetic (TM) polarizations, showing well-pronounced optical resonant modes. The results showed a dominance of whispering gallery modes that were in good agreement with the calculated refractive index. The quality factor (Q) and finesse (F) were estimated, which demonstrated the quality of Li:ZnO structures as optical cavities