Surface and physicochemical characterization of phosphates vivianite, Fe2(PO4)3 and hydroxyapatite, Ca5(PO4)3OH

"Hydroxyapatite is a calcium phosphate in the apatite group. It has numerous applications due to its particular properties including the sorption of metallic ions. This makes it useful for the treatment of contaminated groundwater and for soil decontamination. The least expensive source of hydroxyapatite for synthesis is bovine bone, since this is a waste material. Vivianite is an iron phosphate which has received little study. Like hydroxyapatite, it has particular properties. This paper describes the method of obtaining these phosphates; calcium phosphate from bovine bone, and iron phosphate by synthesis. Also described are the methods of purifying the materials and characterization of these two phosphates by X-ray diffraction, infrared analysis, thermogravimetric and differential scanning calorimetric analysis, scanning electron microscopy, and surface area by the BET method. Physicochemical characteristics of hydroxyapatite obtained from bovine bone are described, and preliminary results are presented of an investigation into whether hydroxyapatite and iron phosphate are suitable as a permeable reactive barrier for the treatment of metallic and radionuclide contaminants.

From radial to unidirectional water pumping in zeta-potential modulated Nafion nanostructures

Chemically propelled micropumps are promising wireless systems to autonomously drive fluid flows for many applications. However, many of these systems are activated by nocuous chemical fuels, cannot operate at high salt concentrations, or have difficulty for controlling flow directionality. In this work we report on a self-driven polymer micropump fueled by salt which can trigger both radial and unidirectional fluid flows. The micropump is based on the cation-exchanger Nafion, which produces chemical gradients and local electric fields capable to trigger interfacial electroosmotic flows. Unidirectional pumping is predicted by simulations and achieved experimentally by nanostructuring Nafion into microarrays with a fine tune modulation of surrounding surface zeta potentials. Nafion micropumps work in a wide range of salt concentrations, are reusable, and can be fueled by different salt cations. We demonstrate that they work with the common water-contaminant cadmium, using the own capture of this ion as fuel to drive fluid pumping. Thus, this system has potential for efficient and fast water purification strategies for environmental remediation. Unidirectional Nafion pumps also hold promise for effective analyte delivery or preconcentration for (bio)sensing assays

SISTEMAS DE ENFRIAMIENTO SECUNDARIO DE UN MOTOR DE COMBUSTION INTERNA (SECONDARY COOLING SYSTEMS OF AN INTERNAL COMBUSTION ENGINE)

Resumen La investigación del presente proyecto es acerca del sistema de enfriamiento de un motor de combustión interna, la idea principal es implementar un sistema de enfriamiento auxiliar debido a que mediante una encuesta el 93% de los usuarios de automóvil han tenido un problema de sobrecalentamiento en el motor de su vehículo, el sistema de enfriamiento auxiliar pretende ayudar el funcionamiento del vehículo aun cuando el sistema principal falle. La primera etapa del proyecto incluye el ensamble de un motor de combustión interna convencional de 350 pulg3, en esta primera etapa se realizó una maqueta del funcionamiento del motor y del sistema de enfriamiento principal, los resultados obtenidos dentro de la primera etapa permiten el funcionamiento correcto del motor, en la segunda etapa se implementará el sistema auxiliar con el objetivo de ahorra dinero en refacciones y servicio de arrastre u otros problemas ocasionados por la falla del sistema de enfriamiento principal. Palabras Clave: Vehículo, Motor de Combustión Interna, Enfriamiento. Abstract The research of this project is about the cooling system of an internal combustion engine, the main idea is to implement an auxiliary cooling system because by means of a survey 93% of car users have had an overheating problem in the Your vehicle's engine, the auxiliary cooling system is intended to assist vehicle operation even when the main system fails. The first stage of the project includes the assembly of a conventional 350 in3 internal combustion engine, in this first stage a model of the operation of the engine and the main cooling system was made, the results obtained within the first stage allow correct operation of the engine, in the second stage the auxiliary system will be implemented in order to save money on spare parts and drag service or other problems caused by the failure of the main cooling system. Keywords: Vehicle, Internal Combustion Engine, Cooling Systems

Mathematical Modeling of Annona Muricata (Guanabana), for Industrialization and Environmental Prevention in Ecuador

Los productos hortofrutícolas de la Amazonía ecuatoriana, los cambios, tecnológicos, las transformaciones actuales y las exigencias del mercado nacional e internacional, atribuyen a una dinámica productiva a la normativa del CODEX STAN 237-2003. Y se enfoca en la modelación matemática para resolver los problemas del aprovechamiento industrial que acarrean en el comercio. Desarrollar la modelación matemática basado en parámetros de volumen, densidad, peso de sus componentes principales de la fruta exótica entera con su categorización de la Annona muricata (Guanábana), Nativa de Mesoamérica. Se desarrolló en el cantón y Provincia Pastaza, considerando su potencial productivo y las Normas del Codex Alimentario y Colombiana I CONTEC. La aplicación fue según la categorización, para el cálculo integral con balances de masas, volumen y densidad mediante análisis estadístico obtenido. El modelo matemático fue en base a sus categorías extra, primera, segunda y residuo de volumen y masa, obteniendo las medias y el coeficiente de variación del 12.59% y con un margen confiabilidad del 99 % y con R2 ajustado del 77%. En relación con su volumen logrando la obtención de nueve fórmulas matemáticas con todas sus constantes (26 – 33), y con una alta confiabilidad del 99%, para su aprovechamiento industrial de esta materia prima, por parte de productores, comerciantes e industriales y estudiantes interesado en esta investigación desarrollada en la Amazonía ecuatoriana.The horticultural products of the Ecuadorian Amazon, the technological changes, the current transformations and the demands of the national and international market, attribute a productive dynamic to the regulations of CODEX STAN 237-2003. And it focuses on mathematical modeling to solve the problems of industrial use that arise in commerce. Develop mathematical modeling based on parameters of volume, density, weight of its main components of the whole exotic fruit with its categorization of the Annona muricata (Soursop), Native to Mesoamerica. Was developed in the Pastaza canton and Province, considering its productive potential and the Standards of the Alimentary Codex and Colombian I CONTEC. The application was according to the categorization, for the comprehensive calculation with mass, volume and density balances through statistical analysis obtained. The mathematical model was based on its extra, first, second and residual categories of volume and mass, obtaining the means and the coefficient of variation of 12.59% and with a reliability margin of 99% and with an adjusted R2 of 77%. In relation to its volume, achieving nine mathematical formulas with all its constants (26 – 33), and with a high reliability of 99%, for the industrial use of this raw material, by producers, merchants, industrialists and students. interested in this research developed in the Ecuadorian Amazon

Caracterización de los factores asociados a nefritis lúpica en el Hospital Universidad del Norte y la Clínica de la Costa en la ciudad de Barranquilla en los años 2008-2018

El lupus eritematoso sistémico (LES) es una enfermedad autoinmune caracterizada por la creación de autoanticuerpos y por la formación de complejos autoinmunes, llevando así a un desequilibrio en la respuesta inmunológica en cualquier órgano del cuerpo. Tiene una mayor prevalencia en el género femenino y suele presentar un inicio insidioso en edades mayores y raza caucásica. Esta patología afecta a las células del cuerpo debido a la formación de complejos de autoanticuerpos que atacan a los diversos tejidos, entre los cuales se encuentra el riñón, causando una patología llamada nefritis lúpica (NL). En el 29% de los pacientes con LES en algún punto de su enfermedad desarrollan NL siendo esta una de sus comorbilidades principales, que aumentan la tasa de mortalidad y empeora el pronóstico de los pacientes. Nuestro trabajo tiene como propósito plasmar los diferentes factores que están relacionados con el desarrollo de esa comorbilidad. El tipo de estudio que se llevará a cabo es observacional descriptivo de tipo transversal. Lo realizaremos a partir de la revisión de historias clínicas entre los años del 2008 al 2018. Se incluirán a los pacientes que cumplan con los criterios de inclusión. Las historias clínicas se tomarán de las bases de datos de la Clínica de la Costa y del Hospital Universidad del Norte y se dispondrá la información utilizando formularios de Google forms. Una vez obtengamos toda esta información se dispondrá en forma de gráficas y tablas para una mayor comprensión.PregradoMedic

Histopatología y bioquímica clínica de ratas expuestas de forma subcrónica al extracto de migración de un material nanocompuesto

Junta de Andalucía AGR5969Ministerio de Ciencia e Innovación AGL2010-2121

Anemia falciforme e gravidez: relato de caso clínico

Sickle cell anemia (SCA) is a pathology with high rates of complications, when presented in pregnancy it is a medical challenge to manage patients due to the high risk of maternal and perinatal morbidity-mortality, case report and review of literature presented at the Hospital Universitario Clínica San Rafael de Bogotá (National Clinic) in 2018, a women in the third trimester of pregnancy with diagnosis of sickle cell anemia that is complicated with preeclampsia with characteristics of severity and preterm delivery.The objective of publishing this case is to review the information regarding the incidence, the maternal and perinatal morbidity / mortality of this medical condition, its management by a multidisciplinary team and the early detection of complications in order to improve the prognosis of the motherchild binomial.La anemia de células falciformes (ACF) es una patología con altos índices de complicaciones; además, cuando se presenta durante el embarazo su manejo se convierte en un desafío médico debido al riesgo elevado de morbimortalidad materna y perinatal. A continuación, se hace una breve revisión de la literatura sobre ACF y se describe un reporte de caso presentado en el Hospital Universitario Clínica San Rafael de Bogotá, Colombia, en el año 2018. La paciente era una primigestante en tercer trimestre del embarazo con diagnóstico de ACF que se complicó con una preeclampsia con características de severidad y concluyó en parto pretérmino. El objetivo de publicar este caso es revisar la información respecto a la incidencia y la morbimortalidad materna y perinatal de la ACF, teniendo en cuenta que debe ser manejada por un equipo multidisciplinario y que se debe hacer detección temprana de complicaciones con el fin de mejorar el pronóstico del binomio madre-hijo.A anemia falciforme (ACF) é uma patologia com altas taxas de complicações; quando ocorre na gravidez, é um desafio médico para gerenciar pacientes devido ao alto risco de morbidade materna e perinatal. Apresenta-se o relato de caso e revisão de literatura apresentada no Hospital Universitário Clínico SanRafael de Bogotá (Clínica Nacional) em 2018, primigestante no terceiro trimestre de gravidez com diagnóstico de anemia falciforme complicada pela pré-eclâmpsia com características de gravidade e parto prematuro.O objetivo da publicação deste caso é revisar as informações referentes à incidência, morbimortalidade materna e perinataldessa condição médica, levando em consideração que ela deve ser gerenciada por uma equipe multidisciplinar e fazer a detecção precoce de complicações, a fim de melhorar o prognóstico binomial: mãe-filho

Violines caucanos: tejido territorial rural-urbano en el norte del Cauca y la ciudad-región de Cali (Colombia)

En el suroccidente colombiano, y en particular entre el norte del Cauca y el sur del Valle, incluyendo el municipio de Buenaventura, con Santiago de Cali como el principal epicentro urbano, se encuentra un amplío entramado de relaciones sociales y vínculos rurales-urbanos que se han consolidado en la región a través de una historia común y un desarrollo socioeconómico y cultural compartido, los cuales conforman un importante tejido territorial. Con un fuerte componente racial en su composición demográfica, este es uno de los territorios de mayor diversidad cultural del país, que se enriquece con expresiones de gran importancia, como las músicas negras andinas en interacción con la música indígena y campesina mestiza andina alrededor de los violines caucanos o violines negros, representativos de las comunidades afro caucanas y del sur del Valle. El presente texto hace visible el tejido territorial de la música nortecaucana, con sus agrupaciones de violines caucanos que se han fortalecido gracias al impulso del Festival de Música del Pacífico Petronio Álvarez, cuyo epicentro de realización cada año es Santiago de Cali.Resumen .-- Introducción .-- I. Santiago de Cali, ciudad región .-- II. El Festival de Música del Pacífico Petronio Álvarez .-- III. Clúster musical y patrimonio cultural inmaterial en el norte del Cauca .-- IV. Conclusiones

Modified Gravity and Cosmology

In this review we present a thoroughly comprehensive survey of recent work on modified theories of gravity and their cosmological consequences. Amongst other things, we cover General Relativity, Scalar-Tensor, Einstein-Aether, and Bimetric theories, as well as TeVeS, f(R), general higher-order theories, Horava-Lifschitz gravity, Galileons, Ghost Condensates, and models of extra dimensions including Kaluza-Klein, Randall-Sundrum, DGP, and higher co-dimension braneworlds. We also review attempts to construct a Parameterised Post-Friedmannian formalism, that can be used to constrain deviations from General Relativity in cosmology, and that is suitable for comparison with data on the largest scales. These subjects have been intensively studied over the past decade, largely motivated by rapid progress in the field of observational cosmology that now allows, for the first time, precision tests of fundamental physics on the scale of the observable Universe. The purpose of this review is to provide a reference tool for researchers and students in cosmology and gravitational physics, as well as a self-contained, comprehensive and up-to-date introduction to the subject as a whole.Comment: 312 pages, 15 figure

Impact of the first wave of the SARS-CoV-2 pandemic on the outcome of neurosurgical patients: A nationwide study in Spain

Objective To assess the effect of the first wave of the SARS-CoV-2 pandemic on the outcome of neurosurgical patients in Spain. Settings The initial flood of COVID-19 patients overwhelmed an unprepared healthcare system. Different measures were taken to deal with this overburden. The effect of these measures on neurosurgical patients, as well as the effect of COVID-19 itself, has not been thoroughly studied. Participants This was a multicentre, nationwide, observational retrospective study of patients who underwent any neurosurgical operation from March to July 2020. Interventions An exploratory factorial analysis was performed to select the most relevant variables of the sample. Primary and secondary outcome measures Univariate and multivariate analyses were performed to identify independent predictors of mortality and postoperative SARS-CoV-2 infection. Results Sixteen hospitals registered 1677 operated patients. The overall mortality was 6.4%, and 2.9% (44 patients) suffered a perioperative SARS-CoV-2 infection. Of those infections, 24 were diagnosed postoperatively. Age (OR 1.05), perioperative SARS-CoV-2 infection (OR 4.7), community COVID-19 incidence (cases/10 5 people/week) (OR 1.006), postoperative neurological worsening (OR 5.9), postoperative need for airway support (OR 5.38), ASA grade =3 (OR 2.5) and preoperative GCS 3-8 (OR 2.82) were independently associated with mortality. For SARS-CoV-2 postoperative infection, screening swab test <72 hours preoperatively (OR 0.76), community COVID-19 incidence (cases/10 5 people/week) (OR 1.011), preoperative cognitive impairment (OR 2.784), postoperative sepsis (OR 3.807) and an absence of postoperative complications (OR 0.188) were independently associated. Conclusions Perioperative SARS-CoV-2 infection in neurosurgical patients was associated with an increase in mortality by almost fivefold. Community COVID-19 incidence (cases/10 5 people/week) was a statistically independent predictor of mortality. Trial registration number CEIM 20/217