Waste tire rubber particles modified by gamma radiation and their use as modifiers of concrete

En este trabajo se produjo concreto añadiendo hule de llantas de desecho, posteriormente se irradió con rayos gamma, para finalmente evaluar sus propiedades mecánicas. Los efectos de la radiación en el hule de llanta se evaluaron con diferentes técnicas analíticas.in this work, cement concrete specimens were produced with cement, water, rock crushed and sand; this last was partially substituted by particles of waste tire rubber. Then the compression properties of the specimens were evaluated following the experimental parameters: a) gamma irradiation dose (200, 250 and 300 kGy), b) particle size of tire rubber (0.85 and 2.8 mm), and c) particulate concentration of tire rubber (1, 3 and 5 wt. %). In addition, the mechanical compression results were related with the changes on the physicochemical properties of the irradiated tire particles, which were analyzed by FT-IR, Raman, UV–vis, SEM, XRD, TGA and DSC

Factibilidad del diseño del sistema de acueducto del casco urbano del corregimiento de Minca, Santa Marta, Magdalena

Un estudio de factibilidad es un instrumento que sirve para orientar la toma de decisiones en la evaluación de un proyecto y corresponde a la última fase de la etapa pre-operativa o de formulación dentro del ciclo del proyecto, previa al diseño del mismo. Este estudio se formula con base en información que tiene la menor incertidumbre posible para medir las posibilidades de éxito o fracaso que tendrá un proyecto de inversión, y para que apoyándose en él se tome la decisión de proceder o no con su implementación. Identificar la necesidad de agua potable en el corregimiento de Minca, Santa Marta, constituye una idea de proyecto digna de ser analizada para así determinar si es factible desarrollar un diseño del sistema de acueducto que satisfaga dicho faltante. Verificar la existencia de un mercado potencial o de una necesidad no satisfecha, demostrar la viabilidad técnica y la disponibilidad de los recursos humanos, materiales, administrativos y financieros, y corroborar las ventajas desde el punto de vista financiero, económico y social de asignar recursos, constituyen, según Miranda , el resumen de los objetivos de cualquier estudio de factibilidad y serán abarcados en este documento para determinar de manera confiable la factibilidad del diseño del sistema de acueducto del casco urbano del corregimiento de Minca, Santa Marta, Magdalena

Integrated electronic system for ultrasonic structural health monitoring

A fully integrated on-board electronic system that can perform in-situ structural health monitoring (SHM) of aircraft?s structures using specifically designed equipment for SHM based on guided wave ultrasonic method or Lamb waves? method is introduced. This equipment is called Phased Array Monitoring for Enhanced Life Assessment (PAMELA III) and is an essential part of overall PAMELA SHM? system. PAMELA III can generate any kind of excitation signals, acquire the response signals that propagate throughout the structure being tested, and perform the signal processing for damage detection directly on the structure without need to send the huge amount of raw signals but only the final SHM maps. It monitors the structure by means of an array of integrated Phased Array (PhA) transducers preferably bonded onto the host structure. The PAMELA III hardware for SHM mapping has been designed, built and subjected to laboratory tests, using aluminum and CFRP structures. The 12 channel system has been designed to be low weight (265 grams only), to have a small form factor, to be directly mounted above the integrated PhA transducers without need for cables and to be EMI protected so that the equipment can be taken on board an aircraft to perform required SHM analyses by use of embedded SHM algorithms. Moreover, the autonomous, automatic and on real-time working procedure makes it suitable for the avionic field, sending the corresponding alerts, maps and reports to external equipment

Seasonal impact of biogenic very short-lived bromocarbons on lowermost stratospheric ozone between 60° N and 60° S during the 21st century

Biogenic very short-lived bromocarbons (VSLBr) currently represent ∼25 % of the total stratospheric bromine loading. Owing to their much shorter lifetime compared to anthropogenic long-lived bromine (e.g. halons) and chlorine (e.g. chlorofluorocarbons), the impact of VSLBr on ozone peaks in the lowermost stratosphere, which is a key climatic and radiative atmospheric region. Here we present a modelling study of the evolution of stratospheric ozone and its chemical loss within the tropics and at mid-latitudes during the 21st century. Two different experiments are explored: considering and neglecting the additional stratospheric injection of 5 ppt biogenic bromine naturally released from the ocean. Our analysis shows that the inclusion of VSLBr results in a realistic stratospheric bromine loading and improves the agreement between the model and satellite observations of the total ozone column (TOC) for the 1980?2015 period at mid-latitudes. We show that the overall ozone response to VSLBr at mid-latitudes follows the stratospheric evolution of long-lived inorganic chlorine and bromine throughout the 21st century. Additional ozone loss due to VSLBr is maximized during the present-day period (1990?2010), with TOC differences of −8 DU (−3 %) and −5.5 DU (−2 %) for the Southern Hemisphere and Northern Hemisphere mid-latitudes (SH-MLs and NH-MLs), respectively. Moreover, the projected TOC differences at the end of the 21st century are ∼50 % lower than the values found for the present-day period.We find that seasonal VSLBr impact on lowermost stratospheric ozone at mid-latitude is influenced by the seasonality of the heterogeneous inorganic-chlorine reactivation processes on ice crystals. Indeed, due to the more efficient reactivation of chlorine reservoirs (mainly ClONO2 and HCl) within the colder SH-ML lowermost stratosphere, the seasonal VSLBr impact shows a small but persistent hemispheric asymmetry through the whole modelled period. Our results indicate that, although the overall VSLBr-driven ozone destruction is greatest during spring, the halogen-mediated (Halogx-Loss) ozone loss cycle in the mid-latitude lowermost stratosphere during winter is comparatively more efficient than the HOx cycle with respect to other seasons. Indeed, when VSLBr are considered, Halogx-Loss dominates wintertime lowermost stratospheric ozone loss at SH-MLs between 1985 and 2020, with a contribution of inter-halogen ClOx?BrOx cycles to Halogx-Loss of ∼50 %.Within the tropics, a small (<−2.5 DU) and relatively constant (∼−1 %) ozone depletion mediated by VSLBr is closely related to their fixed emissions throughout the modelled period. By including the VSLBr sources, the seasonal Halogx-Loss contribution to lowermost stratospheric ozone loss is practically dominated by the BrOx cycle, reflecting the low sensitivity of very short-lived (VSL) bromine to background halogen abundances to drive tropical stratospheric ozone depletion. We conclude that the link between biogenic bromine sources and seasonal changes in heterogeneous chlorine reactivation is a key feature for future projections of mid-latitude lowermost stratospheric ozone during the 21st century.Fil: Barrera, Javier Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Interdisciplinario de Ciencias Básicas. - Universidad Nacional de Cuyo. Instituto Interdisciplinario de Ciencias Básicas; ArgentinaFil: Fernandez, Rafael Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Interdisciplinario de Ciencias Básicas. - Universidad Nacional de Cuyo. Instituto Interdisciplinario de Ciencias Básicas; Argentina. Consejo Superior de Investigaciones Científicas; España. Universidad Tecnológica Nacional; ArgentinaFil: Iglesias Suarez, Fernando. Consejo Superior de Investigaciones Científicas; EspañaFil: Cuevas, Carlos Alberto. Consejo Superior de Investigaciones Científicas; EspañaFil: Lamarque, Jean Francois. National Center for Atmospheric Research; Estados UnidosFil: Saiz-lopez, Alfonso. Consejo Superior de Investigaciones Científicas; Españ

Structural health monitoring network system with wireless communications inside closed aerospace structures

Structural Health Monitoring (SHM) requires integrated "all in one" electronic devices capable of performing analysis of structural integrity and on-board damage detection in aircraft?s structures. PAMELA III (Phased Array Monitoring for Enhanced Life Assessment, version III) SHM embedded system is an example of this device type. This equipment is capable of generating excitation signals to be applied to an array of integrated piezoelectric Phased Array (PhA) transducers stuck to aircraft structure, acquiring the response signals, and carrying out the advanced signal processing to obtain SHM maps. PAMELA III is connected with a host computer in order to receive the configuration parameters and sending the obtained SHM maps, alarms and so on. This host can communicate with PAMELA III through an Ethernet interface. To avoid the use of wires where necessary, it is possible to add Wi-Fi capabilities to PAMELA III, connecting a Wi-Fi node working as a bridge, and to establish a wireless communication between PAMELA III and the host. However, in a real aircraft scenario, several PAMELA III devices must work together inside closed structures. In this situation, it is not possible for all PAMELA III devices to establish a wireless communication directly with the host, due to the signal attenuation caused by the different obstacles of the aircraft structure. To provide communication among all PAMELA III devices and the host, a wireless mesh network (WMN) system has been implemented inside a closed aluminum wingbox. In a WMN, as long as a node is connected to at least one other node, it will have full connectivity to the entire network because each mesh node forwards packets to other nodes in the network as required. Mesh protocols automatically determine the best route through the network and can dynamically reconfigure the network if a link drops out. The advantages and disadvantages on the use of a wireless mesh network system inside closed aerospace structures are discussed

Importance of university teacher behaviour in the faculty of health science

BackgroundWe describe the results from the questionnaire of Tuncel concerning the behaviour of university teachers, since university students believe they have influenced their academic achievement.AimsThe objective of this study was to reveal which behaviours of university teachers were most appreciated by the students in the first year of the studies taught at the Faculty of Health Sciences of Universidad Rey Juan Carlos in Madrid (Degrees in Medicine, Nursing, Physiotherapy, Dentistry, Psychology and Occupational Therapy).Methods 540 first-year students from the Health Sciences degree participated. An exploratory factor analysis of the items was performed and the internal consistency was studied using Cronbach’s alpha.ResultsStudents placed the most importance on the following areas: “Emotional aptitude of the university teacher”, “University teacher-student interaction”, “Achievement of teaching objectives”, “Connection between the teaching of theory and practical components”, “Organization and planning of teaching” and “Correct students and providing them with information on their progress and evolution”. It should be noted that affective factors and the relationship and close interaction with students were the areas most demanded and valued by the students.ConclusionMaking the teaching process more effective is an important goal of educational research. But few researchers take into account the point of view of the students and are primarily involved in determining the behaviour of university teachers. Therefore our aim in this study was to find out their opinions. We wanted to know which attitudes are the most valued by students of the Rey Juan Carlos University (Madrid, Spain) studying for degrees in the health sciences program. Once identified, we will be able to use this information to identify teaching strategies that could improve the minimum academic requirements of the university

Tropospheric Chemical Impact of Considering a Surrogate vs. an Explicit VSLBr Mechanism on the O3 and HOx Distributions within the CAM-Chem model

The contribution of very short-lived bromine (VSLBr) represent 5 ± 2 ppt (∼25%) of total stratospheric bromine (WMO, 2018), which is still nowadays dominated by long-lived bromocarbons that do not impact on tropospheric chemistry. Due to their shorter lifetimes, the overall injection to the stratosphere of VSLBr compounds possesses two distinct pathways: i) Source Gas Injection (SGI), where the brominated species are injected as they were emitted at the surface; and ii) Product Gas Injection (PGI), where the photochemical processing of reactive species arising from SG degradation must be considered. Depending on the partitioning and distribution of SGI and PGI, the chemical impact of VSLBr on tropospheric and lowermost stratospheric ozone, HOx and other oxidizing species can be very different. Many Chemistry Climate Models (CCMs) include a simplified treatment of tropospheric VSLBr sources by assuming a long-lived halocarbon (usually CH3Br) as a Surrogate for VSLBr. Even though these surrogate models possess a consistent evolution of the stratospheric bromine loading, CCMs including an explicit VSLBr representation compare better with organic and inorganic bromine observations in the lowermost stratosphere (Wales et al., 2018). Here we used the halogenated version of the CAM-Chem model (Fernandez et al., 2014) to evaluate the chemical impact of considering an explicit treatment of VSLBr versus considering a simplified tropospheric treatment of long-lived CH3Br as surrogate of VSLBr. The explicit mechanism considers a full gas- and aerosol- phase chemical scheme (including sea-salt dehalogenation) as well as time dependent and geographically-distributed VSLBr emissions inventory (Ordoñez et al., 2012), which replaces the typical lower-boundary surface conditions for longlived compounds usually considered in CCMs. An additional baseline simulation neglecting the contribution of VSLBr is also considered. First we show the differences in the overall inorganic bromine (Bry) burden as a function of altitude, latitude and time of the year, and compare the model changes on SGI and PGI for each model configuration. Based on the vertical and latitudinal Bry distributions, we focus the analysis on determining the surrogate vs. explicit VSLBr impact on the tropospheric ozone burden, as well as the changes in HOx and NOx mixing ratios within different regions. In particular, seasonal variations in the Odd-Oxygen chemical loss channels during within the marine boundary layer (MBL), tropical tropopause layer (TTL) and mid-latitudes upper troposphere (UT) are evaluated. Our results indicate that the impact of VSLBr species is strongly underestimated when a simplified treatment of tropospheric VSLBr chemistry is considered, which might have strong climatic impacts.Fil: Fernández, Rafael Pedro. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales. Departamento de Física; Argentina. Consejo Superior de Investigaciones Científicas. Instituto de Química Física; España. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; ArgentinaFil: Barrera, Javier Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales. Departamento de Física; ArgentinaFil: Iglesias Suarez, Fernando. Consejo Superior de Investigaciones Científicas. Instituto de Química Física; EspañaFil: Cuevas, Carlos Alberto. Consejo Superior de Investigaciones Científicas. Instituto de Química Física; EspañaFil: Kinnison, Douglas E.. No especifíca;Fil: Lamarque, Jean Francoise. No especifíca;Fil: Tilmes, Simone. No especifíca;Fil: Wales, Pamela. University of Maryland; Estados UnidosFil: Nicely, Julie M.. No especifíca;Fil: Salawitch, Ross J.. University of Maryland; Estados UnidosFil: Saiz Lopez, Alfonso. Consejo Superior de Investigaciones Científicas. Instituto de Química Física; España. University of Maryland; Estados UnidosEGU General Assembly 2019VienaAustriaEuropean Geosciences Unio

Burden of Respiratory Failure in Pediatric Patients: Analysis of a Prospective Multicenter Cohort in Bogotá, Colombia

BACKGROUND AND AIMS: The approach to the burden of disease is a demographic, economic, and a health problem, which requires the design and application of specific measures of cost of the disease, such as disability-adjusted life years (DALYs), to establish better public health policies in the pediatric population. The aim of this study is to approach the burden of disease in children with acute respiratory failure (ARF) through the calculation of DALYs. METHODS: This study was conducted in the framework of a prospective, multicenter cohort in Bogotá, Colombia. Inclusion criteria were all pediatric patients admitted to the emergency department, hospitalization, and intensive care unit with respiratory distress; eligible patients were all those who developed ARF between April 2020 and December 2021. They were followed-up during hospitalization, at 30 and 60 days after admission. The Infant/Toddler Quality of Life Questionnaire and KIDSCREEN quality of life scales were applied for follow-up according to the age group. The results were used to calculate DALYs. RESULTS: Six hundred and eighty-five eligible patients, 296 (43.08%) developed ARF, of these 22 (6.08%) patients died (mortality rate = 7.43%). The total DALYs was 277.164 years. For younger than 9 years, the DALYs were 302.64 years, while for older than 10 years were 40.49 years. CONCLUSION: ARF is one of the main causes of preventable mortality in pediatrics, its progression to respiratory failure is a highly prevalent condition in pediatric age, a condition that has a great impact on mortality, morbidity, and disability in our patients

Comportamientos del profesor universitario y éxito académico de los estudiantes de los grados de maestro de infantil y primaria

 It´s disturbing to think about the idea that the teacher can lead a student to achieve great successes or, on the contrary, beat him academically. It´s for this reason that it´s necessary to explore the behavior of teaching professionals, from the point of view of the student, to know which ones they consider that will impact positively on their academic success. In order to this, a sample of 486 pupils from grades Primary Education Teachers (199) and Primary (287) in the Faculty of Education of Albacete (University of Castilla La Mancha) Education was analized. A questionnaire (Tuncel, 2009) (from few questions and the type of response ) was applied and, using a Factor Analysis Exploratory, there were found six dimensions to which the students gave the highest importance: "Emotional aptitude of teachers " ; " Teacher-student interaction " ; " Achieving the goals of education" , "Connecting between teaching of theory and practices " ; "Planning and organization of teaching " ; "Correct and provide information to students about their advance and progress." Es inquietante la idea de pensar que el profesor puede conseguir que un alumno alcance grandes éxitos o que, por el contrario se hunda académicamente.Es por ello por lo que se hace necesario explorar los comportamientos de los profesionales de la enseñanza en la Educación superior, desde el punto de vista del alumno, para conocer cuáles son los que ellos consideran que repercutirán de forma positiva en su éxito académico.Para ello se contó con una muestra de 486 alumnos, pertenecientes a los grados de Maestros de Educación Infantil (199) y Educación Primaria (287) en la Facultad de Educación de Albacete (Universidad de Castilla la Mancha).Se aplicó  un cuestionario (Tuncel, 2009)  y mediante un Análisis Factorial exploratorio, aparecieron seis dimensiones a las cuales los alumnos le otorgaron la mayor importancia, siendo estas: “Aptitud emocional de los profesores”; “Interacción profesor-alumno”; “Lograr y conseguir los objetivos de la enseñanza”, “Conexión durante la instrucción de la teoría con las practicas”; “Planificación y organización  de la docencia”; “Corregir y proporcionar informaciones a los alumnos de sus avances y progresos”

Use of High-Flow Cannula in Pediatric Patients With Respiratory Failure: A Prospective Cohort Study in Three High-Altitude Hospitals

BACKGROUND AND AIMS: Acute respiratory failure (ARF) is a common cause of morbimortality, and a frequent reason for admission to the pediatric intensive care unit (PICU). It requires a high-flow oxygen device as treatment. Our aim is to determine the frequency and main indications for the use of high-flow nasal cannula (HFNC), and the prevalence of HFNC failure and its main causes, in three hospitals. METHODS: It is a multicenter prospective cohort study, developed in three hospitals in Bogota. Eligible patients were children older than 1 month and younger than 18 years who presented ARF and required management with an HFNC. The study was carried out between April 2020 and December 2021. The follow-up was carried out at 1, 6, and 48 h after starting the management. RESULTS: Of 685 patients included in the study, 296 developed ARF. The prevalence of patients with ARF who required management with HFNC was 48%. The frequency of the pathologies that cause the ARF was: Bronchiolitis was the most frequent pathology (34.5%), followed by asthmatic crisis (15.5%) and pneumonia (12.7%). The average time of use of HFNC was 81.6 h. Regarding treatment failure with HFNC, 15 patients presented torpid evolution and required invasive mechanical ventilation, with a prevalence of therapeutic failure of the HFNC of 10.6%. CONCLUSION: The use of HFNC is more frequent in patients with bronchiolitis, in children under 2 years of age and in males, which is in line with what has been reported in the literature. In addition, the failure rate of HFNC is low (10.6%), and it may be useful in other pathologies besides bronchiolitis, such as asthma, pneumonia, among others. It opens the possibility to continue evaluating the role of HFNC in pediatric pathology in new studies