57 research outputs found

    The role of Tris(2-carboxyethyl)phosphine reducing agent in the controlled formation of α,ω-Alkanedithiols Monolayers on Au(111) with monocoordinated and bicoordinated configurations

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    The addition of the reducing agent tris(2-carboxyethyl) phosphine (TCEP) during the formation of α,ω-alkanedithiols monolayers on Au(111) using the immersion method produces the assembly of monolayers with bicoordinated molecules (both S-terminal groups bound to the surface) that have a reductive desorption potential that is more positive than for monolayers with monocoordinated molecules in a standing up configuration. We show that the use of TCEP either during formation of the monolayer or as a post treatment procedure allows the controlled formation of monolayers with bicoordinated or monocoordinated configurations. Density Functional Theory (DFT) calculations were performed to elucidate the role of TCEP in the formation of the bicoordinated configuration. We investigated the TCEP-dithiol interaction in ethanol solvent as well as the coadsorption of trimethylphosphine with 1,2-ethanedithiol on Au(111). The Brønsted base character of the phosphine facilitates the H exchange from the −SHgroups of the dithiol to the phosphorous atom of TCEP with very low activation energy barriers, thus allowing the thiolate groups to bind to the Au(111) surface, thus yielding the bicoordinated configuration. Dithiol lifting mechanisms such as H exchange between S atoms and the formation of intra/inter layer disulfide bonds have much higher energy barriers.Fil: Euti, Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Velez, Patricio. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Matemática y Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Leiva, Ezequiel Pedro Marcos. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Matemática y Física; ArgentinaFil: Macagno, Vicente Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Paredes Olivera, Patricia. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Matemática y Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Patrito, Eduardo Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Cometto, Fernando Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentin

    Super-Nernstian Shifts of Interfacial Proton-Coupled Electron Transfers : Origin and Effect of Noncovalent Interactions

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    The support of the University of Aberdeen is gratefully acknowledged. C.W. acknowledges a summer studentship from the Carnegie Trust for the Universities of Scotland. E.P.M.L. acknowledges SeCYT (Universidad Nacional de Cordoba), ́ CONICET- PIP 11220110100992, Program BID (PICT 2012-2324), and PME 2006-01581 for financial support.Peer reviewedPostprin

    Sistema de Gestión y Control de Cumplimiento de Actividades Docentes basados en el Syllabus para Colegios

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    Este proyecto busca gestionar y mejorar el control de actividades a los docentes de las instituciones educativas, permitiendo realizar una adecuada planificación del contenido de las materias impartidas. La tecnología hoy en día es pieza clave para el proceso aprendizaje enseñanza, en los centros educativos, esto permite tener un mejor mecanismo para realizar los diferentes procesos pedagógicos. GeCCAD, es un sistema web desarrollado para mejorar la interacción pedagógica; tiene herramientas tecnológicas que busca tener como resultado, profesionales con un perfil competitivo, soportando la metodología a utilizar y ayudar a las instituciones a cumplir sus objetivos educacionales, como es el de cumplir con el contenido de las materias asignadas a cada docente. Mediante el uso de estas herramientas se busca llevar un control sobre las actividades realizadas en el proceso de enseñanza por los docentes dentro de la institución y el avance del contenido de las materias impartidas por el mismo. GeCCAD, es la marca comercial del sistema cuyo significado es “Sistema de Gestión y Control de Cumplimiento de Actividades Docentes”, desarrollado en una arquitectura Cliente Servidor (Server Customer Architecture), utiliza como lenguaje ASP.Net y VB.Net, como base de datos MySQL que integra las actividades de gestión académica planificadas y controlar la ejecución y cumplimiento para mejorar el proceso de enseñanza aprendizaje beneficiando a la institución, al docente, al alumno y su representado al tener acceso a la información respecto al desempeño académico.This project aims to manage and improve the control of activities to teachers in educational institutions, enabling proper planning the content of the subjects taught. Today technology is key to the teaching learning process in schools; it allows a better mechanism for different pedagogical processes. GeCCAD, is a web-based system developed to improve pedagogical interaction, is looking to have technological tools as a result, professionals with a competitive, supporting the methodology used and help institutions to meet their educational objectives, such as to comply with the content of the subjects assigned to each teacher. By using these tools you are looking to keep tabs on activities in the teaching by teachers within the institution and progress of the content of the subjects taught by the same GeCCAD, is the trademark system which means "System Management and Compliance Control Teaching Activities" developed in a Client Server (Customer Server Architecture), used as ASP.Net and VB.Net language as a basis for MySQL database that integrates academic management activities planned and controlling the execution and compliance to improve the teaching-learning process to benefit the institution, the teacher, the student and his client to have access to information regarding academic performance

    Factores de riesgo y estrategias de prevención en la desnutrición infantil en Latinoamérica

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    Introduction: In Latin America, child malnutrition persists as a public health challenge, affecting the physical and cognitive development of children. This problem is linked to a complex network of risk factors that include limited access to nutritious foods, unfavorable socioeconomic conditions and educational deficiencies in nutrition. Object of study: Identify risk factors and prevention strategies in child malnutrition in Latin America. Methodology: The research was of documentary design and the type of study is explanatory and bibliographic. Results: It was evident that child malnutrition present in countries such as Venezuela, Colombia, Ecuador, Paraguay, Peru and Cuba, directly affects cognitive development and quality of life forever and presents risk factors such as poverty, education, basic services, sociodemographics, among others. These are responsible for the negative impact on the growth, development and functioning of the body in minors. Likewise, they focus on strategies such as prevention and food education campaigns for the population, digital training, or also through posters, brochures, brochures, to improve knowledge about malnutrition in people and be able to reduce it. Conclusion: Child malnutrition persists as an urgent challenge that affects the comprehensive development of children. To effectively address this problem, it is essential to implement comprehensive strategies that include improvements in access to nutritious foods, favorable socioeconomic conditions, and nutrition education programs.Introducción: En Latinoamérica, la desnutrición infantil persiste como un desafío de salud pública, afectando el desarrollo físico y cognitivo de los niños. Esta problemática está vinculada a una compleja red de factores de riesgo que incluyen limitado acceso a alimentos nutritivos, condiciones socioeconómicas desfavorables y carencias educativas en nutrición. Objeto de estudio: Identificar los factores de riesgo y estrategias de prevención en la desnutrición infantil en Latinoamérica. Metodología: La investigación fue de diseño documental y el tipo de estudio es explicativo y bibliográfico. Resultados: Se evidenció que la desnutrición infantil presente en países como Venezuela, Colombia, Ecuador, Paraguay, Perú y Cuba, afecta directamente el desarrollo cognitivo y calidad de vida para siempre y presentan factores de riesgo como la pobreza, educación, servicios básicos, sociodemográficos, entre otros. Estos son responsables del impacto negativo al crecimiento, desarrollo y funcionamiento del organismo en los menores. De igual forma se centran en estrategias como campañas de prevención y educación alimentaria para la población, capacitaciones de forma digital, o también por medio de carteles, folletos, trípticos, para mejorar el conocimiento sobre la desnutrición en las personas y poder disminuirla. Conclusión: La desnutrición infantil persiste como un desafío urgente que afecta el desarrollo integral de los niños. Para abordar eficazmente este problema, es esencial implementar estrategias integrales que incluyan mejoras en el acceso a alimentos nutritivos, condiciones socioeconómicas favorables y programas educativos en nutrició

    Bcl-2 functionally interacts with inositol 1,4,5-trisphosphate receptors to regulate calcium release from the ER in response to inositol 1,4,5-trisphosphate

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    Inositol 1,4,5-trisphosphate (InsP3) receptors (InsP3Rs) are channels responsible for calcium release from the endoplasmic reticulum (ER). We show that the anti-apoptotic protein Bcl-2 (either wild type or selectively localized to the ER) significantly inhibited InsP3-mediated calcium release and elevation of cytosolic calcium in WEHI7.2 T cells. This inhibition was due to an effect of Bcl-2 at the level of InsP3Rs because responses to both anti-CD3 antibody and a cell-permeant InsP3 ester were decreased. Bcl-2 inhibited the extent of calcium release from the ER of permeabilized WEHI7.2 cells, even at saturating concentrations of InsP3, without decreasing luminal calcium concentration. Furthermore, Bcl-2 reduced the open probability of purified InsP3Rs reconstituted into lipid bilayers. Bcl-2 and InsP3Rs were detected together in macromolecular complexes by coimmunoprecipitation and blue native gel electrophoresis. We suggest that this functional interaction of Bcl-2 with InsP3Rs inhibits InsP3R activation and thereby regulates InsP3-induced calcium release from the ER

    Massive testing in the Galapagos Islands and low positivity rate to control SARS-CoV-2 spread during the first semester of the COVID-19 pandemic: a story of success for Ecuador and South America

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    Introduction: During the first months of the COVID-19 pandemic in Latin America, countries like Ecuador, Peru and Colombia experienced chaotic scenarios with public health systems collapsing and lack of testing capacity to control the spread of the virus. In main cities like Guayaquil in Ecuador, dramatic situations such as corpses in the streets were internationally broadcasted. Methods: While the COVID-19 pandemic was devastating South America, SARS-CoV-2 transmission was successfully managed in the Galapagos Islands due to the implementation of a massive screening strategy including hospitalized and community-dwelling populations, and travel restrictions facilitated by its geographical location (972 km from the Ecuadorian continental territory). Floreana Island was one of the few locations in the world that remained COVID-19 free during 2020. Results: In this study, we retrospectively analyzed the data related to SARS-CoV-2 massive testing campaigns from April to September 2020 in the Galapagos Islands, and found this territory to have the lowest positivity rate in South America (4.8-6.7%) and the highest testing ratio among Ecuadorian provinces (9.87% of the population, which is 2480 out of 25 124 inhabitants) during the first wave of the COVID-19 pandemic. Conclusion: This story of success was possible because of the interinstitutional collaboration between the regional government of Galapagos Islands (Consejo de Gobierno), the local authorities (Gobiernos Autonomos Descentralizados de Santa Cruz, San Cristobal and Isabela), the regional authorities from Ecuadorian Ministry of Health, the Agencia de Regulación y Control de la Bioseguridad y Cuarentena para Galápagos and Universidad de Las Américas

    Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

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    Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p<0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p<0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised

    Los principios tributarios frente a la Ley de Remisión Tributaria en la legislación ecuatoriana

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    1.Marco teórico. --2.Metodologia. --3.ResultadosEl objetivo del presente estudio, se centra en el análisis de los principios tributarios frente a las leyes de remisión tributaria; dado que, todos los Estados sin excepción alguna, necesitan de la contribución de sus habitantes para poder cumplir con su fin supremo, que se resume en el bien común de todos los ciudadanos. En este sentido, a lo largo de la historia durante los diferentes periodos gubernamentales, se han expedido decretos que contemplaron la remisión de ciertos tributos en beneficio de una parte o la totalidad de habitantes del país según correspondía el caso. Con este preámbulo, la metodología empleada esta dado bajo un enfoque cualitativo, apoyada por una investigación bibliográfica y de campo, donde la primera ayudó a sustentar de forma teórica las variables de estudio (principios tributarios y remisión tributaria), mientras que la segunda permitió al investigador internarse en la realidad del problema a través de la recolección de información, para ello fue necesario aplicar un focusgroup a los sujetos investigativos que en este caso fueron los principales funcionarios del Instituto Ecuatoriano de Derecho Tributario. Bajo este contexto y como principales hallazgos, se pudo determinar que la aplicación de los principios tributarios es imparcial; dado que, en ciertas circunstancias, se violentan de forma desconsidera los principios tributarios, sobre todo, el principio de igualdad, asimismo, la remisión de impuestos en el Ecuador, a pesar de que benefició a un gran número de personas y empresas en su última instauración en el año 2018, su aplicación violento una vez más, los principales principios tributarios ecuatorianos, que a priori, son respetados por el resto del colectivo que si paga sus impuestos dentro de los plazos establecidos.Pontificia Universidad Católica del Ecuador, Escuela de JurisprudenciaAbogado/
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