52 research outputs found

    SIMULACIÓN FEM DEL PROCESO DE FORMADO DE TUBO DE ACERO AISI 1018

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    La simulación por elemento finito de procesos de estampado es una herramienta auxiliar en el proceso de diseño y optimización de herramentales. En este artículo se presenta el análisis del proceso de formado de un tubo de acero AISI 1018 mediante un troquel progresivo de dos etapas. Se utilizó ANSYS/LS-DYNA para realizar las simulaciones de tipo dinámico explícito, considerando las diversas no linealidades que implican este tipo de análisis, derivadas de las propiedades del material, las grandes deformaciones y los contactos entre las herramientas y la pieza de trabajo. Los resultados obtenidos son la fuerza máxima requerida para el proceso de formado inicial que fue de 1.27 toneladas y los esfuerzos máximos que se generan en el proceso de doblez que fueron de 76 213 psi. Se muestra, además, la geometría resultante del proceso de formado comparada de forma cualitativa con la obtenida mediante la simulación.Palabra(s) Clave(s): Formado, Método del elemento finito, Simulación

    Caracterização do processo de pirólise de resíduos de polistireno expandido

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    From the different existing methods for plastic recycling, pyrolysis offers the possibility of solving mechanical recycling limitations, which requires large amounts of clean, separate and homogeneous plastic waste in order to be able to guarantee the quality of the final product. In pyrolysis, it is not necessary to classify or clean the different types of plastic waste and it is possible to process waste contaminated with food and chemical products, such as insecticides, herbicides and fertilizers, reducing classification and cleaning costs. Pyrolysis consists of the chemical decomposition of plastic materials by thermal degradation in the absence of oxygen. In this work the results obtained from the pyrolysis ofwaste expanded polystyrene (EPS) in a batch reactor, varying the pyrolysis temperature are presented. It was experimented with a mass of 500 g and temperatures of 350, 400 and 450 ° C. The results indicate that the highest conversion performance in to liquid hydrocarbon was obtained at a temperature of 450 ° C. The lowest yield of liquid hydrocarbon was obtained at the temperature 350 ° C.De los diferentes métodos existentes para el reciclaje de plástico, la pirólisis ofrece la posibilidad de resolver las limitaciones del reciclado mecánico, el cual necesita grandes cantidades de residuos plásticos limpios, separados y homogéneos para poder garantizar la calidad del producto final. En la pirólisis, no es necesaria la clasificación ni limpieza de los distintos tipos de residuos plásticos y es posible procesar residuos contaminados con alimentos y productos químicos, como insecticidas, herbicidas y fertilizantes, reduciendocostos de clasificación y limpieza. La pirólisis consiste en la descomposición química de los materiales plásticos por degradación térmica en ausencia de oxígeno. En este trabajo se presentan los resultados obtenidos de la pirólisis de residuos de poliestireno expandido (EPS) en un reactor tipo batch, variando la temperatura de pirólisis. Se experimentó con una masa de 500 g y temperaturas de 350, 400 y 450 °C. Los resultados indican que el mayor rendimiento de conversión en hidrocarburo líquido fue a una temperatura de 450 °C. El menor rendimiento de hidrocarburo líquido se obtuvo a la temperatura de 350 °C.Dos diferentes métodos existentes para a reciclagem do plástico, a pirólise oferece a possibilidade de resolver as limitações da reciclagem mecânica, na qual requerse grandes quantidades de resíduos plásticos limpos, separados e homogéneos para garantir a qualidade do produto final. Na pirólise, não é necessário classificar ou limpar os diferentes tipos de resíduos plásticos e é possível processar resíduos contaminados com alimentos e produtos químicos, como inseticidas, herbicidas e fertilizantes, reduzindo os custos de classificação e limpeza. A pirólise consiste na decomposição química de materiais plásticos por degradação térmica na ausência de oxigênio. Este trabalho apresenta os resultados obtidos da pirólise de resíduos de poliestireno expandido (EPS) em um reator tipo batelada, alterando a temperatura de pirólise. Os teste forem realizados com uma massa de 500 g e temperaturas de 350, 400 e 450 ° C. Os resultados indicam que a maior eficiência de conversão em hidrocarboneto líquido foi a uma temperatura de 450 ° C. O menor rendimento de hidrocarboneto líquido foi obtido a uma temperatura de 350 ° C

    Staging Parkinson's Disease Combining Motor and Nonmotor Symptoms Correlates with Disability and Quality of Life.

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    Introduction: In a degenerative disorder such as Parkinson's disease (PD), it is important to establish clinical stages that allow to know the course of the disease. Our aim was to analyze whether a scale combining Hoehn and Yahr's motor stage (H&Y) and the nonmotor symptoms burden (NMSB) (assessed by the nonmotor symptoms scale (NMSS)) provides information about the disability and the patient's quality of life (QoL) with regard to a defined clinical stage. Materials and methods: Cross-sectional study in which 603 PD patients from the COPPADIS cohort were classified according to H&Y (1, stage I; 2, stage II; 3, stage III; 4, stage IV/V) and NMSB (A: NMSS = 0-20; B: NMSS = 21-40; C: NMSS = 41-70; D: NMSS ≥ 71) in 16 stages (HY.NMSB, from 1A to 4D). QoL was assessed with the PDQ-39SI, PQ-10, and EUROHIS-QOL8 and disability with the Schwab&England ADL (Activities of Daily Living) scale. Results: A worse QoL and greater disability were observed at a higher stage of H&Y and NMSB (p < 0.0001). Combining both (HY.NMSB), patients in stages 1C and 1D and 2C and 2D had significantly worse QoL and/or less autonomy for ADL than those in stages 2A and 2B and 3A and 3B, respectively (p < 0.005; e.g., PDQ-39SI in 1D [n = 15] vs 2A [n = 101]: 28.6 ± 17.1 vs 7.9 ± 5.8; p < 0.0001). Conclusion: The HY.NMSB scale is simple and reflects the degree of patient involvement more accurately than the HΨ Patients with a lower H&Y stage may be more affected if they have a greater NMS burden

    Staging Parkinson’s Disease Combining Motor and Nonmotor Symptoms Correlates with Disability and Quality of Life

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    COPPADIS Study Group.[Introduction] In a degenerative disorder such as Parkinson’s disease (PD), it is important to establish clinical stages that allow to know the course of the disease. Our aim was to analyze whether a scale combining Hoehn and Yahr’s motor stage (H&Y) and the nonmotor symptoms burden (NMSB) (assessed by the nonmotor symptoms scale (NMSS)) provides information about the disability and the patient’s quality of life (QoL) with regard to a defined clinical stage.[Materials and Methods] Cross-sectional study in which 603 PD patients from the COPPADIS cohort were classified according to H&Y (1, stage I; 2, stage II; 3, stage III; 4, stage IV/V) and NMSB (A: NMSS = 0–20; B: NMSS = 21–40; C: NMSS = 41–70; D: NMSS ≥ 71) in 16 stages (HY.NMSB, from 1A to 4D). QoL was assessed with the PDQ-39SI, PQ-10, and EUROHIS-QOL8 and disability with the Schwab&England ADL (Activities of Daily Living) scale.[Results] A worse QoL and greater disability were observed at a higher stage of H&Y and NMSB (). Combining both (HY.NMSB), patients in stages 1C and 1D and 2C and 2D had significantly worse QoL and/or less autonomy for ADL than those in stages 2A and 2B and 3A and 3B, respectively (; e.g., PDQ-39SI in 1D [n = 15] vs 2A [n = 101]: 28.6 ± 17.1 vs 7.9 ± 5.8; ).[Conclusion] The HY.NMSB scale is simple and reflects the degree of patient involvement more accurately than the H&Y. Patients with a lower H&Y stage may be more affected if they have a greater NMS burden.Peer reviewe

    Challenge B: Human sciences in transition scenarios

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    Coordinators: Josep Martí Pérez (IMF, CSIC), Idoia Murga Castro (IH, CSIC).This challenge is formulated in terms of “humanities in transition,” that is, their approach and articulation in the face of the changes they must undergo to achieve the social weight that, due to their intrinsic relevance, should correspond to them. Faced with these situations that would demand a reinforcement in research and dissemination in diverse aspects of the humanities, from multiple perspectives, paradoxically an adverse panorama is drawn for the development and dissemination of humanistic knowledge, which concerns different factors. Some are related to the consideration of the area of knowledge itself, its organization within the scientific system, the questioning of its own limits, and the interaction with another knowledge. Considering current transition scenarios does not mean having to abandon old objectives, but it adds to the work conducted new objects of study closely related to current reality, such as: the informational revolution; the relations with the ecosystem and the environmental crisis; globalization; the intensification of human mobility and migration flows; the growing economic and social inequality; the frictions derived from the articulation of collective identities; the decolonization of discourses; demographic dynamics; integration of technological advances; and viability and support for alternative models of society.Peer reviewe

    Clustering COVID-19 ARDS patients through the first days of ICU admission. An analysis of the CIBERESUCICOVID Cohort

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    Background Acute respiratory distress syndrome (ARDS) can be classified into sub-phenotypes according to different inflammatory/clinical status. Prognostic enrichment was achieved by grouping patients into hypoinflammatory or hyperinflammatory sub-phenotypes, even though the time of analysis may change the classification according to treatment response or disease evolution. We aimed to evaluate when patients can be clustered in more than 1 group, and how they may change the clustering of patients using data of baseline or day 3, and the prognosis of patients according to their evolution by changing or not the cluster.Methods Multicenter, observational prospective, and retrospective study of patients admitted due to ARDS related to COVID-19 infection in Spain. Patients were grouped according to a clustering mixed-type data algorithm (k-prototypes) using continuous and categorical readily available variables at baseline and day 3.Results Of 6205 patients, 3743 (60%) were included in the study. According to silhouette analysis, patients were grouped in two clusters. At baseline, 1402 (37%) patients were included in cluster 1 and 2341(63%) in cluster 2. On day 3, 1557(42%) patients were included in cluster 1 and 2086 (57%) in cluster 2. The patients included in cluster 2 were older and more frequently hypertensive and had a higher prevalence of shock, organ dysfunction, inflammatory biomarkers, and worst respiratory indexes at both time points. The 90-day mortality was higher in cluster 2 at both clustering processes (43.8% [n = 1025] versus 27.3% [n = 383] at baseline, and 49% [n = 1023] versus 20.6% [n = 321] on day 3). Four hundred and fifty-eight (33%) patients clustered in the first group were clustered in the second group on day 3. In contrast, 638 (27%) patients clustered in the second group were clustered in the first group on day 3.Conclusions During the first days, patients can be clustered into two groups and the process of clustering patients may change as they continue to evolve. This means that despite a vast majority of patients remaining in the same cluster, a minority reaching 33% of patients analyzed may be re-categorized into different clusters based on their progress. Such changes can significantly impact their prognosis

    5to. Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad. Memoria académica

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    El V Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad, CITIS 2019, realizado del 6 al 8 de febrero de 2019 y organizado por la Universidad Politécnica Salesiana, ofreció a la comunidad académica nacional e internacional una plataforma de comunicación unificada, dirigida a cubrir los problemas teóricos y prácticos de mayor impacto en la sociedad moderna desde la ingeniería. En esta edición, dedicada a los 25 años de vida de la UPS, los ejes temáticos estuvieron relacionados con la aplicación de la ciencia, el desarrollo tecnológico y la innovación en cinco pilares fundamentales de nuestra sociedad: la industria, la movilidad, la sostenibilidad ambiental, la información y las telecomunicaciones. El comité científico estuvo conformado formado por 48 investigadores procedentes de diez países: España, Reino Unido, Italia, Bélgica, México, Venezuela, Colombia, Brasil, Estados Unidos y Ecuador. Fueron recibidas un centenar de contribuciones, de las cuales 39 fueron aprobadas en forma de ponencias y 15 en formato poster. Estas contribuciones fueron presentadas de forma oral ante toda la comunidad académica que se dio cita en el Congreso, quienes desde el aula magna, el auditorio y la sala de usos múltiples de la Universidad Politécnica Salesiana, cumplieron respetuosamente la responsabilidad de representar a toda la sociedad en la revisión, aceptación y validación del conocimiento nuevo que fue presentado en cada exposición por los investigadores. Paralelo a las sesiones técnicas, el Congreso contó con espacios de presentación de posters científicos y cinco workshops en temáticas de vanguardia que cautivaron la atención de nuestros docentes y estudiantes. También en el marco del evento se impartieron un total de ocho conferencias magistrales en temas tan actuales como la gestión del conocimiento en la universidad-ecosistema, los retos y oportunidades de la industria 4.0, los avances de la investigación básica y aplicada en mecatrónica para el estudio de robots de nueva generación, la optimización en ingeniería con técnicas multi-objetivo, el desarrollo de las redes avanzadas en Latinoamérica y los mundos, la contaminación del aire debido al tránsito vehicular, el radón y los riesgos que representa este gas radiactivo para la salud humana, entre otros

    The evolution of the ventilatory ratio is a prognostic factor in mechanically ventilated COVID-19 ARDS patients

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    Background: Mortality due to COVID-19 is high, especially in patients requiring mechanical ventilation. The purpose of the study is to investigate associations between mortality and variables measured during the first three days of mechanical ventilation in patients with COVID-19 intubated at ICU admission. Methods: Multicenter, observational, cohort study includes consecutive patients with COVID-19 admitted to 44 Spanish ICUs between February 25 and July 31, 2020, who required intubation at ICU admission and mechanical ventilation for more than three days. We collected demographic and clinical data prior to admission; information about clinical evolution at days 1 and 3 of mechanical ventilation; and outcomes. Results: Of the 2,095 patients with COVID-19 admitted to the ICU, 1,118 (53.3%) were intubated at day 1 and remained under mechanical ventilation at day three. From days 1 to 3, PaO2/FiO2 increased from 115.6 [80.0-171.2] to 180.0 [135.4-227.9] mmHg and the ventilatory ratio from 1.73 [1.33-2.25] to 1.96 [1.61-2.40]. In-hospital mortality was 38.7%. A higher increase between ICU admission and day 3 in the ventilatory ratio (OR 1.04 [CI 1.01-1.07], p = 0.030) and creatinine levels (OR 1.05 [CI 1.01-1.09], p = 0.005) and a lower increase in platelet counts (OR 0.96 [CI 0.93-1.00], p = 0.037) were independently associated with a higher risk of death. No association between mortality and the PaO2/FiO2 variation was observed (OR 0.99 [CI 0.95 to 1.02], p = 0.47). Conclusions: Higher ventilatory ratio and its increase at day 3 is associated with mortality in patients with COVID-19 receiving mechanical ventilation at ICU admission. No association was found in the PaO2/FiO2 variation

    La organización y atención a la diversidad en centros de educación secundaria de Iberoamérica. Reflexiones y experiencias

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    La organización y atención a la diversidad en centros de educación secundaria de Iberoamérica. Reflexiones y experiencias" es el nuevo título de la Serie Informes de RedAGE. La misma recoge la visión de 41 especialistas de 13 países iberoamericanos sobre la realidad y perspectivas de la atencion a la diversidad en centros de educación secundaria. La focalización, en esta etapa educativa, tiene que ver con la consideración de que, actualmente, es el momento de la escolarización donde se producen más abandonos y donde se abren o limitan posibilidades para el posible acceso a estudios superiores de los más capacitados. La orientación de los escritos tiene que ver con las finalidades y objetivos de la Red de Apoyo a la Gestion Educativa (RedAGE); también con el convencimiento, por parte de los que escriben, de que el contexto organizativo actúa como un amplificador o limitador de las actuaciones dirigidas a la formación de los escolares

    Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)

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    Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters. Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs). Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001). Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio
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