53 research outputs found

    A Finite Element‑Based Methodology for the Thermo‑mechanical Analysis of Early Age Behavior in Concrete Structures

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    This paper presents a general procedure based on fracture mechanics models in order to analyze the level of cracking and structural safety in reinforced concrete elements at early ages, depending on the stripping time. Our procedure involves the development of a thermo-mechanical numerical model based on the finite element method that accounts for the change in the mechanical properties of concrete with time. Moreover, fracture mechanisms are analyzed by means of a material damage model, which is characterized via specific experimental results obtained for standard specimens and notched beams under three-point bending testing. The loading conditions are both thermal and mechanical, and are obtained from the hydration process for a given concrete dosage. The presented methodology allows for the determination of the optimal stripping time, whereas it helps assessing the analysis of the cracking and the stress states of the elements under consideration. A practical application, namely the analysis of a retaining wall, is used to validate our methodology, showing its suitability in engineering practice.Ministerio de Economía y Competitividad BIA2016-75431-

    Propuesta de evaluación del aprendizaje en materias científico-técnicas

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    El presente trabajo pretende mostrar un sistema de evaluación que se lleva acabo en materias científico-técnicas donde el contenido práctico es considerable. Se pretende considerar los distintos instrumentos y formas de evaluación del aprendizaje de los estudiantes. El objetivo principal de este trabajo pretende entender que examinar y calificar no son actos de menor importancia, sino que suponen una gran influencia en todo el proceso y pueden o no, ayudar y animar a los estudiantes en su principal tarea del aprendizaje y su progreso. La propuesta permite desarrollar las siguientes técnicas docentes: sesiones académicas teóricas, prácticas, exposición y debate, seminarios y jornadas, tutorías colectivas y además visitas facultativas

    Propuesta de evaluación del aprendizaje en materias científico-técnicas

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    El presente trabajo pretende mostrar un sistema de evaluación que se lleva acabo en materias científico-técnicas donde el contenido práctico es considerable. Se pretende considerar los distintos instrumentos y formas de evaluación del aprendizaje de los estudiantes. El objetivo principal de este trabajo pretende entender que examinar y calificar no son actos de menor importancia, sino que suponen una gran influencia en todo el proceso y pueden o no, ayudar y animar a los estudiantes en su principal tarea del aprendizaje y su progreso. La propuesta permite desarrollar las siguientes técnicas docentes: sesiones académicas teóricas, prácticas, exposición y debate, seminarios y jornadas, tutorías colectivas y además visitas facultativas

    Relação entre bem-estar social, gênero e outros fatores sociodemográficos

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    Resumen: Introducción: En la actualidad se ha demostrado que el bienestar social representa un factor psicosocial de gran relevancia para el contexto académico en diversidad de niveles educativos. El objetivo de este estudio fue analizar el bienestar social percibido de adolescentes y otros factores sociodemográficos, como el género o el nivel académico de los padres y madres. Se realizó un estudio no experimental de carácter descriptivo y corte transversal mediante una única medición en un único grupo. La muestra estuvo representada por 128 estudiantes adolescentes (de 12 a 18 años de edad) de un centro público de Córdoba. Como instrumento se aplicó la escala de bienestar social desarrollada por Blanco y Díaz (2005) obteniéndose una fiabilidad aceptable de α = 0,822, empleándose para el análisis de los datos el software IBM SPSS. Los resultados indicaron niveles adecuados de bienestar social de forma global, siendo el género algo masculino algo superior al femenino. Asimismo, el género masculino estaba asociado a unos mayores niveles de actualización social, al igual que unos mayores niveles de contribución y coherencia social en función de los estudios de los padres y las madres respectivamente. Todo ello, revela la consideración de dichos factores sociodemográficos a la hora de intervenir y trabajar el bienestar social en jóvenes adolescentes.Abstract: Introduction: Nowadays, it has been shown that social well-being represents a psychosocial factor of great relevance for the academic context in several educational levels. The objective of this study was to analyze the perceived social well-being of adolescents and other sociodemographic factors, such as gender or the academic level of fathers and mothers. A non-experimental descriptive and cross-sectional study was carried out by means of a single measurement in a single group. The sample was represented by 128 adolescent students (12 to 18 years old) from a public high school from Córdoba. As main instrument, the social well-being scale developed by Blanco y Díaz (2005) was applied, obtaining an acceptable reliability of α = 0.822, and using the IBM SPSS software for data analysis. The results indicated adequate levels of social well-being in a global way, with gender being somewhat masculine rather than feminine. Likewise, the masculine gender was associated with higher levels of social updating, as well as higher levels of contribution and social coherence according to the studies of the fathers and mothers respectively. All this reveals the consideration of these sociodemographic factors when intervening and working on social well-being in young adolescents.Resumo: Introdução: Atualmente, tem sido demonstrado que o bem-estar social representa um fator psicossocial de grande relevância para o contexto acadêmico em uma diversidade de níveis educacionais. O objetivo deste estudo foi analisar o bem-estar social percebido de adolescentes e outros fatores sociodemográficos, como gênero ou nível acadêmico de pais e mães. Um estudo descritivo e transversal não experimental foi realizado por meio de uma única medida em um único grupo. A amostra foi representada por 128 estudantes adolescentes (12 a 18 anos) de um centro público em Córdoba. Como instrumento, foi aplicada a escala de bem-estar social desenvolvida por Blanco y Díaz (2005), obtendo-se uma confiabilidade aceitável de α = 0,822, utilizando o software IBM SPSS para análise de dados. Os resultados indicaram níveis adequados de bem-estar social de maneira global, com gênero sendo um tanto masculino e não feminino. Da mesma forma, o gênero masculino esteve associado a maiores níveis de atualização social, assim como maiores níveis de contribuição e coerência social, de acordo com os estudos dos pais e mães, respectivamente. Tudo isso revela a consideração desses fatores sociodemográficos ao intervir e trabalhar no bem-estar social em adolescentes jovens

    PELIGROSIDAD A LOS MOVIMIENTOS DE LADERA EN LA VERTIENTE MERIDIONAL DE SIERRA NEVADA (GRANADA) A PARTIR DE LA ESTIMACIÓN MULTI-TÉCNICA DE LA ACTIVIDAD

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    El presente trabajo aborda la cartografía de la susceptibilidad y la peligrosidad a los movimientos de ladera, en un ambiente montañoso, con información limitada sobre su actividad. El análisis y validación de la susceptibilidad se realizada mediante un modelo elaborado a partir del ModelBuilder™ de ArcGIS basado en el Método de la Matriz en un SIG. Dicho modelo necesita una cartografía previa de los movimientos, un MDE y un análisis discriminante de los factores determinantes de la estabilidad. Los datos del análisis reflejan que el 15% de la zona estudiada muestra una susceptibilidad a los movimientos de moderada a muy alta que, a su vez, coincide con lugares donde se encuentran la mayoría de las infraestructuras públicas de la región. Además, los valores registrados en la validación mediante el grado de ajuste están por encima del 83% para las zonas de susceptibilidad alta y muy alta. Estas zonas que presentan un mayor grado de susceptibilidad y, por tanto, una mayor exposición potencial al riesgo, son las seleccionadas para el análisis detallado de la peligrosidad. El principal problema, que, por otra parte, suele ser generalizado en este tipo de áreas para la estimación de la frecuencia con la que se suceden movimientos de ladera, es la falta de información sobre su ocurrencia. Por tanto, y con el objetivo de obtener la mayor información posible, los datos relativos a la actividad de los movimientos se extraen de diversas fuentes y técnicas, de forma que interactivamente solventen sus correspondientes limitaciones. Estos datos se extraen de una documentación previa, tanto en prensa como bibliografía específica, donde se presentan trabajos sobre DInSAR, fotogrametría aérea y LIDAR, y TLS. Además, se realiza de forma específica un análisis dendrogeomorfológico de árboles en movimientos de ladera y se revisa la ortofotografía aérea histórica de la zona de estudio. Posteriormente, con los datos de actividad, se realiza un análisis de los factores desencadenantes, que refleja que los movimientos de ladera están relacionados con episodios de precipitaciones intensas y prolongadas, y no tanto con la actividad sísmica del área. Por último, de forma indirecta, se estima la peligrosidad de la zona de estudio a los movimientos de ladera, asociando los resultados obtenidos de actividad con los factores desencadenantes; esto es, con periodos de precipitaciones intensas. Así, se establece un periodo de retorno que se extrapola a toda el área, con la asunción de que los grandes deslizamientos se generan o reactivan, conjuntamente con movimientos superficiales, tras periodos lluviosos intensos y prolongados, y que las lluvias torrenciales generan movimientos de ladera superficiales tipo flujo y desprendimientos. Los resultados obtenidos indican que la frecuencia con la que se generan los movimientos es de 5 años para los flujos superficiales y desprendimientos (F=0,2), y de 18 años para los deslizamientos y movimientos complejos (F=0,06). La zona, en términos generales, presenta determinados sectores con susceptibilidad moderada a muy alta, sin embargo la peligrosidad a los movimientos de ladera es de moderada a muy baja. En términos de probabilidad temporal, los flujos y desprendimientos son los movimientos con mayor peligrosidad

    Assessment of the Evolution of a Landslide Using Digital Photogrammetry and LiDAR Techniques in the Alpujarras Region (Granada, Southeastern Spain)

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    In this work a detailed analysis of the temporal evolution of the Almegíjar landslide is presented. It is a rock slide located in the Alpujarras region (Granada, Spain) that has developed over the last 30 years. Six datasets and photogrammetric flights corresponding to the years 1956, 1984, 1992, 2001, 2008, and 2010 were surveyed. The more recent flight of 2010 combined an aerial digital camera and a LiDAR sensor and was oriented by means of in-flight data and tie points. This 2010 flight allowed for the generation of a reliable and high-precision Digital Terrain Model (DTM). The other flights were oriented using second-order ground control points transferred from the 2010 flight, and the corresponding DTMs were prepared by automatic matching and subsequent editing from the stereoscopic models. After comparing the DTMs of different dates, it has been observed that the landslide was triggered after 1984 and since then has evolved in an irregular pattern with periods of variable activity. On average, the ground surface dropped more than 8 m in depleted zones and rose nearly 4 m in the accumulation zones, with a velocity catalogued as very slow (about 15–30 cm/year) over a time span corresponding to a degree VIII of diachroneity. The total volume of the mobilized mass of this large contemporary slide was about 300 × 103 m3.This research was funded by the projects P06-RNM-02125 and RNM-06862 (ISTEGEO) funded by the Andalusian Research Plan, projects CGL2008-04854 and TIN2009-09939 funded by the Ministry of Science and Innovation of Spain and Research Groups TEP-213, and RNM 221 of the Andalusian Research Plan

    GEICAM Guidelines for the Management of Patients with Breast Cancer During the COVID-19 Pandemic in Spain

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    Breast cancer (BC) is the most common cancer in women in Spain. During the COVID-19 pandemic caused by the SARSCoV-2 virus, patients with BC still require timely treatment and follow-up; however, hospitals are overwhelmed with infected patients and, if exposed, patients with BC are at higher risk for infection and serious complications if infected. Thus, health care providers need to evaluate each BC treatment and in-hospital visit to minimize pandemic-associated risks while maintaining adequate treatment efficacy. Here we present a set of guidelines regarding available options for BC patient management and treatment by BC subtype in the context of the COVID-19 pandemic. Owing to the lack of evidence about COVID-19 infection, these recommendations are mainly based on expert opinion, medical organizations’ and societies’ recommendations, and some published evidence. We consider this a useful tool to facilitate medical decision making in this health crisis situation we are facing

    Kinetics of humoral immune response over 17 months of COVID-19 pandemic in a large cohort of healthcare workers in Spain : the ProHEpiC-19 study

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    Understanding the immune response to the SARS-CoV-2 virus is critical for efficient monitoring and control strategies. The ProHEpic-19 cohort provides a fine-grained description of the kinetics of antibodies after SARS-CoV-2 infection with an exceptional resolution over 17 months. We established a cohort of 769 healthcare workers including healthy and infected with SARS-CoV-2 in northern Barcelona to determine the kinetics of the IgM against the nucleocapsid (N) and the IgG against the N and spike (S) of SARS-CoV-2 in infected healthcare workers. The study period was from 5 May 2020 to 11 November 2021.We used non-linear mixed models to investigate the kinetics of IgG and IgM measured at nine time points over 17 months from the date of diagnosis. The model included factors of time, gender, and disease severity (asymptomatic, mild-moderate, severe-critical) to assess their effects and their interactions. 474 of the 769 participants (61.6%) became infected with SARS-CoV-2. Significant effects of gender and disease severity were found for the levels of all three antibodies. Median IgM(N) levels were already below the positivity threshold in patients with asymptomatic and mild-moderate disease at day 270 after the diagnosis, while IgG(N and S) levels remained positive at least until days 450 and 270, respectively. Kinetic modelling showed a general rise in both IgM(N) and IgG(N) levels up to day 30, followed by a decay with a rate depending on disease severity. IgG(S) levels remained relatively constant from day 15 over time. IgM(N) and IgG(N, S) SARS-CoV-2 antibodies showed a heterogeneous kinetics over the 17 months. Only the IgG(S) showed a stable increase, and the levels and the kinetics of antibodies varied according to disease severity. The kinetics of IgM and IgG observed over a year also varied by clinical spectrum can be very useful for public health policies around vaccination criteria in adult population. Regional Ministry of Health of the Generalitat de Catalunya (Call COVID19-PoC SLT16_04; NCT04885478). The online version contains supplementary material available at 10.1186/s12879-022-07696-6

    Proposed global prognostic score for systemic mastocytosis: a retrospective prognostic modelling study

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    [Background]: Several risk stratification models have been proposed in recent years for systemic mastocytosis but have not been directly compared. Here we designed and validated a risk stratification model for progression-free survival (PFS) and overall survival (OS) in systemic mastocytosis on the basis of all currently available prognostic factors, and compared its predictive capacity for patient outcome with that of other risk scores.[Methods]: We did a retrospective prognostic modelling study based on patients diagnosed with systemic mastocytosis between March 1, 1983, and Oct 11, 2019. In a discovery cohort of 422 patients from centres of the Spanish Network on Mastocytosis (REMA), we evaluated previously identified, independent prognostic features for prognostic effect on PFS and OS by multivariable analysis, and designed a global prognostic score for mastocytosis (GPSM) aimed at predicting PFS (GPSM-PFS) and OS (GPSM-OS) by including only those variables that showed independent prognostic value (p<0·05). The GPSM scores were validated in an independent cohort of 853 patients from centres in Europe and the USA, and compared with pre-existing risk models in the total patient series (n=1275), with use of Harrells' concordance index (C-index) as a readout of the ability of each model to risk-stratify patients according to survival outcomes.[Findings]: Our GPSM-PFS and GPSM-OS models were based on unique combinations of independent prognostic factors for PFS (platelet count ≤100 × 109 cells per L, serum β2-microglobulin ≥2·5 μg/mL, and serum baseline tryptase ≥125 μg/L) and OS (haemoglobin ≤110 g/L, serum alkaline phosphatase ≥140 IU/L, and at least one mutation in SRSF2, ASXL1, RUNX1, or DNMT3A). The models showed clear discrimination between low-risk and high-risk patients in terms of worse PFS and OS prognoses in the discovery and validation cohorts, and further discrimination of intermediate-risk patients. The GPSM-PFS score was an accurate predictor of PFS in systemic mastocytosis (C-index 0·90 [95% CI 0·87–0·93], vs values ranging from 0·85 to 0·88 for pre-existing models), particularly in non-advanced systemic mastocytosis (C-index 0·85 [0·76–0·92], within the range for pre-existing models of 0·80 to 0·93). Additionally, the GPSM-OS score was able to accurately predict OS in the entire cohort (C-index 0·92 [0·89–0·94], vs 0·67 to 0·90 for pre-existing models), and showed some capacity to predict OS in advanced systemic mastocytosis (C-index 0·72 [0·66–0·78], vs 0·64 to 0·73 for pre-existing models).[Interpretation]: All evaluated risk classifications predicted survival outcomes in systemic mastocytosis. The REMA-PFS and GPSM-PFS models for PFS, and the International Prognostic Scoring System for advanced systemic mastocytosis and GPSM-OS model for OS emerged as the most accurate models, indicating that robust prognostication might be prospectively achieved on the basis of biomarkers that are accessible in diagnostic laboratories worldwide.Carlos III Health Institute, European Regional Development Fund, Spanish Association of Mastocytosis and Related Diseases, Rare Diseases Strategy of the Spanish National Health System, Junta of Castile and León, Charles and Ann Johnson Foundation, Stanford Cancer Institute Innovation Fund, Austrian Science Fund
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