Kinetic study of methanol dehydration over Zro2 supported-activated carbons

The growing concerns about climate change and energy consumption have been the driving force in seek of alternative fuels such as DME, mainly produced via methanol dehydration over a solid acid catalyst. The use of activated carbons for this aim has been little studied up to date. Only a few studies can be found in the literature, reporting all of them materials with a low thermal stability of the acid surface groups, which results into a fast deactivation of the catalyst. In this work, the preparation of activated carbons via chemical activation with phosphoric acid, their modification with different ZrO2 loads, and their application as methanol dehydration catalysts have been studied. The catalytic results showed that the best methanol conversion and selectivity towards DME were achieved with the activated carbon prepared with an impregnation mass ratio value (H3PO4 /precursor) of 2 and an activation temperature of 800 ºC, loaded with a 7 % (wt) of ZrO2 . This catalyst exhibits high steady state methanol conversion values even at temperatures as high as 400 ºC (XCH3OH= 80%, 0.1 g·s/μmol, PCH3OH= 0.08 atm in helium), keeping a selectivity to DME higher than 96%. The effect of oxygen in the reaction atmosphere was also analysed. In this sense, an increase of 15 % in the DME yield was obtained when using air instead of helium as reaction atmosphere (350 ºC, 0.1 g·s/μmol, PCH3OH= 0.04 atm). A kinetic study has been carried out on this catalyst in which two mechanisms (Eley Rideal and Langmuir Hinshelwood) for methanol dehydration have been analysed. The models proposed also consider the presence of oxygen in the reaction media.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. MINECO (CTQ2015-68654-R). MECD (FPU13/02413)

Biomass derived activated carbon catalysts for the one-step dimethyl ether synthesis from syngas

Se trata de un resumen extendido de una comunicación a congreso internacional.In this work we study the behaviour of a carbon-based catalyst for this one-step synthesis process. Two kinds of activated carbons, prepared by chemical (with H3PO4) and physical (by CO2 partial gasification) activation of olive stones, were used as catalysts support. The main difference between the activated carbons was the presence of chemically stable phosphorus surface groups, mainly in form of C-O-PO3 groups1, on the activated carbon prepared via chemical activation. The addition of Zr to the chemically activated carbon (ACPZr) resulted in the formation of zirconium phosphate species on the carbon surface, which were capable of promoting the selective methanol dehydration to DME. Cu-Zn loading on the chemically activated carbon resulted in strong interactions between the metallic phase and the phosphate surface groups due to the formation Cu phosphate species. The bifunctional catalyst, ACPZrCuZn showed less conversion that the physical mixture. This fact is related with the presence of phosphorus species that avoids the reduction of the metal (copper).Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Planificación para la implantación de un Sistema de Gestión de la Calidad en el RAAA 74: Definición de Fases y Responsabilidades

Actualmente todo el mundo sabe de la importancia que posee la calidad en el Ejército de Tierra, sin ella las unidades de fuerza terrestre serían incapaces de ejercer sus cometidos con unas garantías de seguridad y aptitud mínimas. No obstante, dicha función de la calidad debe gestionarse para lograr llegar a su objetivo. Debido a lo expuesto en este proyecto se ha investigado como se implantaría un Sistema de Gestión de la Calidad en la Unidad de Reparaciones III/ 74, San Roque, la cual es encargada de ejercer las funciones logísticas en el Regimiento de Artillería Antiaérea 74 sobre todo lo relacionado del sistema HAWK.Para la realización de este trabajo se va a comenzar dando unas nociones básicas sobre definiciones y principios a día de hoy que plantea la norma ISO 9001:2015 para un SGC; ya que sobre estos se van a desarrollar. Acto seguido se van a describir los objetivos y metodología que se va a seguir en este TFG para su desarrollo; así como el contexto de la unidad donde se ha desarrollado e investigado. Sobre esta última se estudiará además el estado en la actualidad en el que se encuentra respecto a su gestión de la calidad, señalando su respectiva problemática, para así entender mejor su elaboración y en qué aspectos se debe centrar el trabajo a desarrollar.En primer lugar se realizará un estudio sobre los procesos que componen el SGC; esto se compondrá primero de una clasificación de ellos en tipos de procesos, ya que no todos los procesos tienen la misma finalidad dentro del sistema .A continuación, se hará una descripción breve de todos ellos, señalando los elementos de entrada y salida de los que se componen; además se desarrollarán unas fichas técnicas de todos los procesos, en los que se describan todos los ámbitos recalcados en la norma que debe contener un proceso de un SGC. Por último se mostrará como interaccionan dichos procesos en el sistema, señalando los vínculos que existen entre los procesos y sus tipos.Por otro lado, se realizará un procedimiento de implantación del SGC, siendo una de las más importantes partes del presente TFG. Este consistirá en una adaptación al Ciclo Gestor del Tiempo [13], en el cual primeramente se definirán las fases de las que va a consistir dicho procedimiento, proporcionando las tareas y herramientas para su realización. En un segundo lugar se van a proporcionar los recursos de los que se va a disponer para dicha implantación, así como la asignación de estos a las distintas responsabilidades a hacer de cada fase. Acto seguido se estimará la duración de las que se va a componer cada fase y el procedimiento en general; estas duraciones servirán para desarrollar el calendario en el que se va a implantar el SGC, estipulando además la secuenciación que tendrán dichas fases en el calendario. En último lugar, se analizarán los principales riesgos a los que está expuesto dicho procedimiento, proporcionando en su caso medidas para su inmediata respuesta.Por último, se desarrollará unas conclusiones de lo que ha supuesto este proyecto, analizando los puntos claves y la problemática surgida en los distintos apartados que suponen. Además se contará alguna de las líneas futuras y recomendaciones posibles para este trabajo.<br /

A novel continual learning approach for competitive neural networks

Continual learning tries to address the stability-plasticity dilemma to avoid catastrophic forgetting when dealing with non-stationary distributions. Prior works focused on supervised or reinforcement learning, but few works have considered continual learning for unsupervised learning methods. In this paper, a novel approach to provide continual learning for competitive neural networks is proposed. To this end, we have proposed a different learning rate function that can cope with non-stationary distributions by adapting the model to learn continuously. Experimental results performed with different synthetic images that change over time confirm the performance of our proposal.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Long-term outcome of patients after a single interruption of antiretroviral therapy: a cohort study

Background: To describe the long term outcome of patients who interrupted highly active antiretroviral therapy (HAART) once, identify the variables associated with earlier need to re-start HAART, and the response when therapy was resumed. A retrospective observational cohort of 66 adult patients with HIV-1 infection who interrupted HAART with a CD4+cell count ≥350 cells/μL and undetectable viral load (VL) was performed. The pre-established CD4+ cell count for restarting therapy was 300cells/μL. Cox regression was used to analyse the variables associated with earlier HAART reinitiation. Results: The median follow-up was 209 weeks (range, 64–395). Rates of HIV-related or possible HIV-related events were 0.37 (one case of acute retroviral syndrome) and 1.49 per 100 patient-years, respectively. Two patients died after re-starting therapy and having reached undetectable VL. Three patients suffered a sexually transmitted disease while off therapy. Fifty patients (76%) resumed therapy after a median of 97 weeks (range, 17–267). Age, a nadir of CD4+ 10,000 copies/ml were independent predictors for earlier re-start. The intention-to-treat success rate of the first HAART resumed regimen was 85.4%. There were no differences by regimen used, nor between regimens that were the same as or different from the one that had been interrupted. Conclusions: Our data suggest highly active antiretroviral therapy may be interrupted in selected patients because in these patients, when the HAART is restarted, the viral and clinical response may be achieved

Cognition and the five-factor model of the Positive and Negative Syndrome Scale in schizophrenia

Different exploratory and confirmatory factorial analyses of the Positive and Negative Syndrome Scale (PANSS) have found a number of factors other than the original positive, negative, and general psychopathology. Based on a review of previous studies and using confirmatory factor analyses (CFA), Wallwork et al. (Schizophr Res 2012; 137: 246–250) have recently proposed a consensus five-factor structure of the PANSS. This solution includes a cognitive factor which could be a useful measure of cognition in schizophrenia. Our objectives were 1) to study the psychometric properties (factorial structure and reliability) of this consensus five-factor model of the PANSS, and 2) to study the relationship between executive performance assessed using the Wisconsin Card Sorting Test (WCST) and the proposed PANSS consensus cognitive factor (composed by items P2-N5-G11). This cross-sectional study included a final sample of 201 Spanish outpatients diagnosed with schizophrenia. For our first objective, CFA was performed and Cronbach's alphas of the five factors were calculated; for the second objective, sequential linear regression analyses were used. The results of the CFA showed acceptable fit indices (NNFI = 0.94, CFI = 0.95, RMSEA = 0.08). Cronbach's alphas of the five factors were adequate. Regression analyses showed that this five-factor model of the PANSS explained more of the WCST variance than the classical three-factor model. Moreover, higher cognitive factor scores were associated with worse WCST performance. These results supporting its factorial structure and reliability provide robustness to this consensus PANSS five-factor model, and indicate some usefulness of the cognitive factor in the clinical assessment of schizophrenic patients

Investigation of the 240Pu(n, f ) reaction at the n_TOF/EAR2 facility in the 9 meV–6 MeV range

Background: Nuclear waste management is considered amongst the major challenges in the field of nuclear energy. A possible means of addressing this issue is waste transmutation in advanced nuclear systems, whose operation requires a fast neutron spectrum. In this regard, the accurate knowledge of neutron-induced reaction cross sections of several (minor) actinide isotopes is essential for design optimization and improvement of safety margins of such systems. One such case is 240 Pu , due to its accumulation in spent nuclear fuel of thermal reactors and its usage in fast reactor fuel. The measurement of the 240 Pu ( n , f ) cross section was previously attempted at the CERN n_TOF facility EAR1 measuring station using the time-of-flight technique. Due to the low amount of available material and the given flux at EAR1, the measurement had to last several months to achieve a sufficient statistical accuracy. This long duration led to detector deterioration due to the prolonged exposure to the high α activity of the fission foils, therefore the measurement could not be successfully completed. Purpose: It is aimed to determine whether it is feasible to study neutron-induced fission at n_TOF/EAR2 and provide data on the 240 Pu ( n , f ) reaction in energy regions requested for applications. Methods: The study of the 240 Pu ( n , f ) reaction was made at a new experimental area (EAR2) with a shorter flight path which delivered on average 30 times higher flux at fast neutron energies. This enabled the measurement to be performed much faster, thus limiting the exposure of the detectors to the intrinsic activity of the fission foils. The experimental setup was based on microbulk Micromegas detectors and the time-of-flight data were analyzed with an optimized pulse-shape analysis algorithm. Special attention was dedicated to the estimation of the non-negligible counting loss corrections with the development of a new methodology, and other corrections were estimated via Monte Carlo simulations of the experimental setup. Results: This new measurement of the 240 Pu ( n , f ) cross section yielded data from 9 meV up to 6 MeV incident neutron energy and fission resonance kernels were extracted up to 10 keV . Conclusions: Neutron-induced fission of high activity samples can be successfully studied at the n_TOF/EAR2 facility at CERN covering a wide range of neutron energies, from thermal to a few MeV.Croatian Science Foundation 857

Propuesta de innovación docente para Filología: programa de inclusión del alumnado en la investigación universitaria y la adquisición de experiencias científicas y formativas

El presente proyecto busca satisfacer la creciente voluntad de participación del alumnado en los procesos y ámbitos académicos profesionales, dinamizando su interacción con el cuerpo docente, así como la apertura de horizontes laborales a nivel universitario. Se incentivará el aprendizaje y la producción personal del alumno mediante la adición de vías participativas más allá de las curriculares, y se reforzará el funcionamiento de aquéllas merced al desarrollo de metodologías donde sus actividades investigadoras y creativas encuentren una respuesta y supervisión más inmediata del profesorado. Estas iniciativas pavimentarán las futuras incursiones académicas del alumno que desee realizarlas y supondrán una mejora en los planteamientos teóricos y prácticos del que participan el resto. Es un proyecto que emana de iniciativas ya existentes tanto entre el alumnado como entre el cuadro docente; sus repercusiones, aunque académicas, son eminentemente prácticas, en tanto que revitalizan la utilidad intelectual, personal y académica del grado y conectan los conocimientos de éste con las ramificaciones que un personal docente transversal es capaz de ofrecer

Health-related quality of life with palbociclib plus endocrine therapy versus capecitabine in postmenopausal patients with hormone receptor–positive metastatic breast cancer: Patient-reported outcomes in the PEARL study

Background: The PEARL study showed that palbociclib plus endocrine therapy (palbociclib/ET) was not superior to capecitabine in improving progression-free survival in postmenopausal patients with metastatic breast cancer resistant to aromatase inhibitors, but was better tolerated. This analysis compared patient-reported outcomes. Patients and methods: The PEARL quality of life (QoL) population comprised 537 patients, 268 randomised to palbociclib/ET (exemestane or fulvestrant) and 269 to capecitabine. Patients completed the European Organisation for Research and Treatment of Cancer QLQC30 and QLQ-BR23 and EQ-5D-3L questionnaires. Changes from the baseline and time to deterioration (TTD) were analysed using linear mixed-effect and stratified Cox regression models, respectively. Results: Questionnaire completion rate was high and similar between treatment arms. Significant differences were observed in the mean change in global health status (GHS)/QoL scores from the baseline to cycle 3 (2.9 for palbociclib/ET vs.-2.1 for capecitabine (95% confidence interval [CI], 1.4-8.6; P = 0.007). The median TTD in GHS/QoL was 8.3 months for palbociclib/ET versus 5.3 months for capecitabine (adjusted hazard ratio, 0.70; 95% CI, 0.55-0.89; P = 0.003). Similar improvements for palbociclib/ET were also seen for other scales as physical, role, cognitive, social functioning, fatigue, nausea/vomiting and appetite loss. No differences were observed between the treatment arms in change from the baseline in any item of the EQ-5D-L3 questionnaire as per the overall index score and visual analogue scale. Conclusion: Patients receiving palbociclib/ET experienced a significant delay in deterioration of GHS/QoL and several functional and symptom scales compared with capecitabine, providing additional evidence that palbociclib/ET is better tolerated. Trial registration number: NCT02028507 (ClinTrials.gov). EudraCT study number: 2013-003170-27. 2021 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)