9 research outputs found

    Structural Evolution of CO2-Filled Pure Silica LTA Zeolite under High-Pressure High-Temperature Conditions

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    [EN] The crystal structure of CO2-filled pure-SiO2 LTA zeolite has been studied at high pressures and temperatures using synchrotron-based X-ray powder diffraction. Its structure consists of 13 CO2 guest molecules, 12 of them accommodated in the large alpha-cages and one in the beta-cages, giving a SiO2/CO2 stoichiometric ratio smaller than 2. The structure remains stable under pressure up to 20 GPa with a slight pressure-dependent rhombohedral distortion, indicating that pressure-induced amorphization is prevented by the insertion of guest species in this open framework. The ambient temperature lattice compressibility has been determined. In situ high-pressure resistive-heating experiments up to 750 K allow us to estimate the thermal expansivity at P approximate to 5 GPa. Our data confirm that the insertion of CO2 reverses the negative thermal expansion of the empty zeolite structure. No evidence of any chemical reaction was observed. The possibility of synthesizing a silicon carbonate at high temperatures and higher pressures is discussed in terms of the evolution of C-O and Si-O distances between molecular and framework atoms.The authors thank the financial support of the Spanish Ministerio de Economia y Competitividad (MINECO), the Spanish Research Agency (AEI), and the European Fund for Regional Development (FEDER) under Grant Nos. MAT2016-75586-C4-1-P, MAT2015-71842-P, Severo Ochoa SEV-2012-0267, and No.MAT2015-71070-REDC (MALTA Consolider). D.S.-P. and J.R.-F. acknowledge MINECO for a Ramon y Cajal and a Juan de la Cierva contract, respectively. Portions of this work were performed at GeoSoilEnviroCARS (Sector 13), Advanced Photon Source (APS), Argonne National Laboratory. GeoSoilEnviroCARS is supported by the National Science Foundation - Earth Sciences (EAR-1128799) and Department of Energy- GeoSciences (DE-FG02-94ER14466). This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. Use of the COMPRES-GSECARS gas loading system was supported by COMPRES under NSF Cooperative Agreement EAR 11-57758. CO2 gas was also loaded at Diamond Light Source. Authors thank synchrotron ALBA-CELLS for beamtime allocation at MSPD line. British Crown Owned Copyright 2017/AWE. Published with permission of the Controller of Her Britannic Majesty's Stationery Office.Santamaria-Perez, D.; Marqueño, T.; Macleod, S.; Ruiz-Fuertes, J.; Daisenberger, D.; Chulia-Jordan, R.; Errandonea, D.... (2017). Structural Evolution of CO2-Filled Pure Silica LTA Zeolite under High-Pressure High-Temperature Conditions. Chemistry of Materials. 29(10):4502-4510. https://doi.org/10.1021/acs.chemmater.7b01158S45024510291

    A Large Multicenter Prospective Study of Community-Onset Healthcare Associated Bacteremic Urinary Tract Infections in the Era of Multidrug Resistance: Even Worse than Hospital Acquired Infections?

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    Introduction: Healthcare-associated (HCA) infections represent a growing public health problem. The aim of this study was to compare community-onset healthcare associated (CO-HCA) bacteremic urinary tract infections (BUTI) and hospital-acquired (HA)-BUTI with special focus on multidrug resistances (MDR) and outcomes. Methods: ITUBRAS-project is a prospective multicenter cohort study of patients with HCA-BUTI. All consecutive hospitalized adult patients with CO-HCA-BUTI or HA-BUTI episode were included in the study. Exclusion criteria were: patients \ 18 years old, non-hospitalized patients, bacteremia from another source or primary bacteremia, non-healthcare related infections and infections caused by unusual pathogens of the urinary tract. Th main outcome variable was 30-day all-cause mortality with day 1 as the first day of positive blood culture. Logistic regression was used to analyze factors associated with clinical cure at hospital discharge and with receiving inappropriate initial antibiotic treatment. Cox regression was used to evaluate 30-day all-cause mortality. Results: Four hundred forty-three episodes were included, 223 CO-HCA-BUTI. Patients with CO-HCA-BUTI were older (p \ 0.001) and had more underlying diseases (p = 0.029) than those with HA-BUTI. The severity of the acute illness (Pitt score) was also higher in CO-HCABUTI (p = 0.026). Overall, a very high rate of MDR profiles (271/443, 61.2%) was observed, with no statistical differences between groups. In multivariable analysis, inadequate empirical treatment was associated with MDR profile (aOR 3.35; 95% CI 1.77?6.35), Pseudomonas aeruginosa (aOR 2.86; 95% CI 1.27?6.44) and Charlson index (aOR 1.11; 95% CI 1.01?1.23). Mortality was not associated with the site of acquisition of the infection or the presence of MDR profile. However, in the logistic regression analyses patients with CO-HCA-BUTI (aOR 0.61; 95% CI 0.40?0.93) were less likely to present clinical cure. Conclusion: The rate of MDR infections was worryingly high in our study. No differences in MDR rates were found between CO-HCA-BUTI and HA-BUTI, in the probability of receiving inappropriate empirical treatment or in 30-day mortality. However, CO-HCA-BUTIs were associated with worse clinical cure.Funding. This study and the journal’s Rapid Service Fee are sponsored and funded by MSD Spain. The study was also supported by Plan Nacional de I+D+i 2013–2016 and Instituto de Salud Carlos III, Subdirección General de Redes y Centros de Investigación Cooperativa, Ministerio de Economía, Industria y Competitividad, Spanish Network for Research in Infectious Diseases (REIPI RD16/0016/0004, RD16/ 0016/0005, RD16/0016/0007, RD16/0016/0010, RD16/0016/0011 and RD16/0016/0015), co-financed by the European Development Regional Fund ‘A way to achieve Europe’ (ERDF), Operative program Intelligent Growth 2014–2020

    A Large Multicenter Prospective Study of Community-Onset Healthcare Associated Bacteremic Urinary Tract Infections in the Era of Multidrug Resistance: Even Worse than Hospital Acquired Infections?

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    Introduction: Healthcare-associated (HCA) infections represent a growing public health problem. The aim of this study was to compare community-onset healthcare associated (CO-HCA) bacteremic urinary tract infections (BUTI) and hospital-acquired (HA)-BUTI with special focus on multidrug resistances (MDR) and outcomes. Methods: ITUBRAS-project is a prospective multicenter cohort study of patients with HCA-BUTI. All consecutive hospitalized adult patients with CO-HCA-BUTI or HA-BUTI episode were included in the study. Exclusion criteria were: patients < 18 years old, non-hospitalized patients, bacteremia from another source or primary bacteremia, non-healthcare-related infections and infections caused by unusual pathogens of the urinary tract. The main outcome variable was 30-day all-cause mortality with day 1 as the first day of positive blood culture. Logistic regression was used to analyze factors associated with clinical cure at hospital discharge and with receiving inappropriate initial antibiotic treatment. Cox regression was used to evaluate 30-day all-cause mortality. Results: Four hundred forty-three episodes were included, 223 CO-HCA-BUTI. Patients with CO-HCA-BUTI were older (p < 0.001) and had more underlying diseases (p = 0.029) than those with HA-BUTI. The severity of the acute illness (Pitt score) was also higher in CO-HCA-BUTI (p = 0.026). Overall, a very high rate of MDR profiles (271/443, 61.2%) was observed, with no statistical differences between groups. In multivariable analysis, inadequate empirical treatment was associated with MDR profile (aOR 3.35; 95% CI 1.77–6.35), Pseudomonas aeruginosa (aOR 2.86; 95% CI 1.27–6.44) and Charlson index (aOR 1.11; 95% CI 1.01–1.23). Mortality was not associated with the site of acquisition of the infection or the presence of MDR profile. However, in the logistic regression analyses patients with CO-HCA-BUTI (aOR 0.61; 95% CI 0.40–0.93) were less likely to present clinical cure. Conclusion: The rate of MDR infections was worryingly high in our study. No differences in MDR rates were found between CO-HCA-BUTI and HA-BUTI, in the probability of receiving inappropriate empirical treatment or in 30-day mortality. However, CO-HCA-BUTIs were associated with worse clinical cure. © 2021, The Author(s)

    Túneles Virtuales: toma de datos en el Metaverso

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    En los últimos años está siendo cada vez más difícil realizar salidas de campo en el ámbito de la ingeniería del terreno. Si a eso sumamos asignaturas como túneles y mecánica de rocas donde la toma de datos se realiza en muchas ocasiones en obras subterráneas y taludes en construcción, las dificultades de obtener permisos y datos realistas son aún mayores. Desde el año 2019 en el Departamento de Ingeniería y Morfología del terreno de la UPM se están desarrollando practicas virtuales (laboratorios y salidas de campo) para que el alumnado pueda tomar por sí mismo los datos que luego harán en ejercicio y prácticas. Se trata de generar una serie de modelos como si fueren un simulador de vuelo tomar datos lo más fidedignos en entornos virtuales. Para ello se han visitado y escaneado obras subterráneas reales tomando datos geotécnicos que luego el alumno replicará. Se ha desarrollado dos tipos de productos: imágenes 3D escaneadas y entornos de Realidad Virtual como si estuviésemos visitando la obra. Iniciados los escenarios en 2019, todo se desarrolló muy rápido y se establecieron colaboraciones con numerosas universidades durante los confinamientos de la pandemia de COVID19 En un principio las practicas virtuales versaron sobre taludes rocosos. En esta ocasión en el curso 2022 – 2023 se están implementando en túneles, tanto en ejecución (clasificaciones geomecánicas y diseño empírico) como en la inspección de túneles existentes. El proyecto incorpora aula invertida, aprendizaje basado en retos y experiencias docentes en el Mataverso – Realidad Virtua

    PAT Ciencias 2017-2018: Adaptaciones curriculares de la Facultad de Ciencias

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    El creciente número de estudiantes con necesidades especiales en las universidades españolas ha dispuesto que se empiecen a tomar medidas para regular la docencia de este tipo de estudiantes. En base a esto, la Universidad de Alicante creó en el año 2015 un documento que regulaba los derechos de estos estudiantes en función de la necesidad que tuvieran, concediéndoles lo que se denomina adaptaciones curriculares. Sin embargo, la implantación de estas adaptaciones no ha sido tarea fácil. La incorporación de una plataforma para gestionarlas ha deshumanizado el proceso. Los estudiantes no se ponen en contacto con los docentes porque piensan que al estar la aplicación no es necesario y, como consecuencia, muchos docentes desconocen quienes son los estudiantes a los que tienen que aplicar la adaptación curricular. Y entre docentes y estudiantes se encuentra el Programa de Acción Tutorial (PAT), que se encarga de hacer de intermediario para controlar que el proceso de adaptación curricular se realice con normalidad. Por este motivo, este curso 2017-2018 el PAT de la Facultad de Ciencias ha querido hacer un estudio del funcionamiento de las adaptaciones curriculares para detectar las posibles deficiencias en el proceso y mejorarlas en cursos posteriores

    PAT Ciencias 2017-2018: Adaptaciones curriculares de la Facultad de Ciencias

    No full text
    El creciente número de estudiantes con necesidades especiales en las universidades españolas ha dispuesto que se empiecen a tomar medidas para regular la docencia de este tipo de estudiantes. En base a esto, la Universidad de Alicante creó en el año 2015 un documento que regulaba los derechos de estos estudiantes en función de la necesidad que tuvieran, concediéndoles lo que se denomina adaptaciones curriculares. Sin embargo, la implantación de estas adaptaciones no ha sido tarea fácil. La incorporación de una plataforma para gestionarlas ha deshumanizado el proceso. Los estudiantes no se ponen en contacto con los docentes porque piensan que al estar la aplicación no es necesario y, como consecuencia, muchos docentes desconocen quienes son los estudiantes a los que tienen que aplicar la adaptación curricular. Y entre docentes y estudiantes se encuentra el Programa de Acción Tutorial (PAT), que se encarga de hacer de intermediario para controlar que el proceso de adaptación curricular se realice con normalidad. Por este motivo, este curso 2017-2018 el PAT de la Facultad de Ciencias ha querido hacer un estudio del funcionamiento de las adaptaciones curriculares para detectar las posibles deficiencias en el proceso y mejorarlas en cursos posteriores

    Assessment of plasma chitotriosidase activity, CCL18/PARC concentration and NP-C suspicion index in the diagnosis of Niemann-Pick disease type C : A prospective observational study

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    Niemann-Pick disease type C (NP-C) is a rare, autosomal recessive neurodegenerative disease caused by mutations in either the NPC1 or NPC2 genes. The diagnosis of NP-C remains challenging due to the non-specific, heterogeneous nature of signs/symptoms. This study assessed the utility of plasma chitotriosidase (ChT) and Chemokine (C-C motif) ligand 18 (CCL18)/pulmonary and activation-regulated chemokine (PARC) in conjunction with the NP-C suspicion index (NP-C SI) for guiding confirmatory laboratory testing in patients with suspected NP-C. In a prospective observational cohort study, incorporating a retrospective determination of NP-C SI scores, two different diagnostic approaches were applied in two separate groups of unrelated patients from 51 Spanish medical centers (n = 118 in both groups). From Jan 2010 to Apr 2012 (Period 1), patients with ≥2 clinical signs/symptoms of NP-C were considered 'suspected NP-C' cases, and NPC1/NPC2 sequencing, plasma chitotriosidase (ChT), CCL18/PARC and sphingomyelinase levels were assessed. Based on findings in Period 1, plasma ChT and CCL18/PARC, and NP-C SI prediction scores were determined in a second group of patients between May 2012 and Apr 2014 (Period 2), and NPC1 and NPC2 were sequenced only in those with elevated ChT and/or elevated CCL18/PARC and/or NP-C SI ≥70. Filipin staining and 7-ketocholesterol (7-KC) measurements were performed in all patients with NP-C gene mutations, where possible. In total across Periods 1 and 2, 10/236 (4%) patients had a confirmed diagnosis o NP-C based on gene sequencing (5/118 [4.2%] in each Period): all of these patients had two causal NPC1 mutations. Single mutant NPC1 alleles were detected in 8/236 (3%) patients, overall. Positive filipin staining results comprised three classical and five variant biochemical phenotypes. No NPC2 mutations were detected. All patients with NPC1 mutations had high ChT activity, high CCL18/PARC concentrations and/or NP-C SI scores ≥70. Plasma 7-KC was higher than control cut-off values in all patients with two NPC1 mutations, and in the majority of patients with single mutations. Family studies identified three further NP-C patients. This approach may be very useful for laboratories that do not have mass spectrometry facilities and therefore, they cannot use other NP-C biomarkers for diagnosis
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